translation from CP437 -> UTF-8 and only when using high-level text output
functions - so the output from native/DOS doors and scripts that use low-level
output methods won't be translated.
UTF-8 is auto-detected (only) at this time during answer (before login) by
sending a ZWNBSP and checking (via ANSI) if the cursor position moved - an
idea "borrowed" from Ozz Nixon (aka SqZ).

This commit requires the new "encode" library (src/encode), so you may need
to perform a cvs checkout to get that module!

- for PETSCII, this is automatic and you don't lose blink, but you do lose
  colored foreground when enabling a bright background ("reverse video")
- for ANSI, this mode is typically referred to as "iCE colors" and disables
  blinking-text support
- Ctrl-AE (^AE) is the new attribute code to enable bright-background
  (will have no effect on ANSI terminals that are not iCE color enabled)
  "E" is now valid in the ctrl/attr.cfg file and string values for JS
  console.attributes assignments, as well
- Ctrl-AI (^AI) - blink - now does nothing for ANSI/ICE color terminals
  (blinking is not supported in combination with bright-background)
- Using a new/non-standard CGA attribute bit-flag to indicate the selection of
  bright-background colors (BG_BRIGHT, bit 10), separate from BLINK.
  This change required all/most char/uchar attribute representations to be
  converted to int/uint.

New text.dat strings:
- PetTerminalDetected (renamed from PetTermDetected)
- PetTerminalQ
- TerminalAutoDetect
- TerminalColumns
- TerminalRows
- TerminalMonochrome
- TerminalColor
- TerminalIceColor
- IceColorTerminalQ
This also moved the MsgCarbonCopyList definition to the end of the file
for now.

PETSCII reverse-video attribute fix:
When a CR is sent to the terminal, the reverse-video attibute is auto-disabled
so update our "current attribute" (curatr) value to match the remote.

Support new printfile/putmsg mode flag: P_WRAP to force an ungraceful
line-wrap (splitting) to the specified column width. If no column width is
specified (0), then this mode will force an ungraceful wrap before the last
terminal column where some terminals *may* auto-wrap.

JS console.printfile() and printtail() methods now support an optional
"orig_columns" argument, similar to console.putmsg(). Must specify P_WORDWRAP
or P_WRAP for this argument to have any effect.

Much improved terminal-type selection/configuration in the user defaults
menu and abort (^C) at any of the yes/no prompts is now detected/handled much
better (to answers to the prompted questions are not saved to the user
settings).

when set, force a clear-to-end-of-line sequence to be sent to the remote
terminal before sending a carriage-return (CR, '\r') character. This is useful
in scenarios where you want to move/home the cursor and *not* clear the screen
and then display or execute something that assumes clean lines are being
displayed on and thus wouldn'd bother with any clear-to-eol sequences before
line-endings.
Any scripts that enable this mode should disable it upon exit (e.g. using
js.on_exit() to restore the original console status).

will be sending 0x7f (DEL) when the backspace key is struck: SWAP_DELETE
For example, xterm sends 0x7f when backspace and hit and an ANSI escape
sequence when the DEL key is hit.

I don't yet have a way to *enable* this setting.

Also, allow the user's setting of NO_EXASCII to take effect even when
auto-terminal type detection is used (yes, the user's terminal can support
ANSI and *not* CP437).

I noticed that printable ctrl chars (e.g. 0x18 and 0x19) were not causing the
current column position to increment, so that got me looking at this code and
wondering why the LF/FF checking was outside the if(!outchar_esc) condition
and being executed when CON_R_ECHO is off. So now, using a switch statement,
it's cleaner and all the printable ctrl chars move the current column position
correctly.

Oct-14-2018:
It turns out, PabloDraw actually inserts a Ctrl-AZ sequence at the end of .msg
(and presumably Synchronet .asc) files it edits - before the SAUCE record.
This resulted in a printed Ctrl-Z character (arrow pointing right) in most
terminals when viewing text/menu files created or edited with PabloDraw. :-(
So, now Ctrl-AZ (uppercase) will revert to the previous definition:
premature end-of-file (EOF)
and a Ctrl-Az (lowercase) will output a Ctrl-Z (substitute) character.
I'm not a big fan of case-sensitive Ctrl-A codes, but frankly, running out of
chars and I already started this pattern with the Ctrl-AF/f sequences.
Hopefully there's no existing software that is/was putting Ctrl-Az (lowercase)
in files, expecting that to trigger a premature EOF. I certainly was not.

now have their output translated to PETSCII equivalents for PETSCII terminals
(but input is not yet translated).
.seq files are now sent untranslated via printfile() and putmsg() to PETSCII
terminals (using the new P_PETSCII putmsg mode flag).
.seq files (and P_PETSCII mode text printed via putmsg) is now converted
(poorly) from PETSCII to CP437 - this is still a work-in-progress.
Remove the remants of WIP and HTMLterm support from putmsg() and printfile().

don't use the stored user terminal type. This allows the same user (e.g.
the sysop) to be logged onto multiple nodes concurrently with different
terminal types without effecting the other node/session.
Guest sessions were already immune to this problem.

So Omegix recently asked in the Synchronet Discussion group whether or not
a PETSCII (Commodore) terminal could be used to access his Synchronet BBS.
Now, the answer is "Yes". :-)
The major issues addressed:

- detecting a PETSCII terminal, solved by assigning specific (configurable):
  TCP ports to be used for incoming PETSCII connections, by default:
  port 64 is for 40-column PETSCII and port 128 is for 80-column PETSCII,
  but if the terminal sends a Telnet Window Size reply (e.g. SyncTERM), then
  either size terminal should fine on either port.
  The port numbers are configurable in the [BBS] section of your sbbs.ini
  file using the new keys: PET40Port (default value: 64) and PET80Port
  (default value: 128). Having these keys set doesn't make make the terminal
  server listen on that additional port - you'll need to add more
  IP:port combinations to one of Interfaces values, example:
    TelnetInterface=71.95.196.34,71.95.196.34:64,71.95.196.34:128
  And you don't have to use Telnet for the PETSCII connections - you could use
  RLogin or SSH instead (or in addition).

- support for terminal widths < 80 columns:
  This was achieved through a combination of text.dat changes (numerous),
  new Ctrl-A and @-codes and new optional terminal-width-specific menu files
  (e.g. text/menu/main.40col.asc)
  A side effect of these changes is actually better support for terminals
  *wider* than 80 columns as well!

- support for terminals that don't expand tabs to spaces (e.g. PETSCII):
  The terminal server now handles tab expansion with a run-time settable
  tab-size (default size: 8)

- conditional access based on PETSCII (or small) terminal use (or not):
  + New PETSCII ARS keyword (boolean)
  + New COLS and ROWS ARS keywords (for terminal width and height requirements)
  + New TERM (string) ARS keyword

New @-codes:
  - WORDWRAP, when placed at the top of a file, enables auto-wordwrap for
              lines longer than the terminal width
  - CENTER, the text following before an end of line will be displayed centered
            on the terminal (whatever the width, in columns)
  - CLEAR, like CLS, except it ignores (doesn't display) a CRLF that follows
  - COLS, current number of terminal columns (width)
  - ROWS, current number of terminal rows (height)
  - TERM, the auto-detected or reported terminal type (e.g. ANSI, TTY, etc.)
  - SYSONLY, toggles "echo" (display) off/back-on for non-sysops
            similar to the Ctrl-A( and ) codes, but more convenient to use
            (and PabloDraw won't strip the @-code from the file like it does
             with Ctrl-A codes it doesn't support)

New Ctrl-A codes:
  - \ conditional new-line/continuation when the terminal width is < 80 cols
      prints the new text.dat string LongLineContinuationPrefix

yesno() will now return true if passed a blank string.
noyes() will now return false if passed a blank string.
getstr()'s input length limiting based on terminal width is more broadly
           applied now (not just when using the K_LINE mode flag).

New JS bbs object method: menu_exists(<base_filename>) returns Boolean
New JS console object property: tabstop (Number)
New JS console object methods: getbyte() and putbyte() to recv/send raw byte
    value with (very little) interpretation/intervention by the terminal server
New JS console object method: creturn() - performs a carriage return
    (or equivalent)
New JS (and C) printfile() mode flag: P_TRUNCATE, causes long lines to be
    truncated, rather than displaying causing a line-wrap.

New text.dat strings:
  - NoAccessTerminal (for ARS check failures)
  - LongLineContinuationPrefix (for breaking long lines for 40col terminals)
  - Scanning (replaces a previously hard-coded "Scanning" string)
  - Done (replaces a previusly hard-coded "Done")
  - Scanned  (when finished scannning, clears the progress bar)

was so pervasive. I hope I don't regret changing this. Ctrl-AZ == Ctrl-Z just
"feels right" while Ctrl-AZ == EOF feels stoopid. :-/

('?' from the Reading Messages prompt) would not fully display because
it contains a Ctrl-Z character (for the right-arrow symbol). Rather than
revert the menu() change (where CPM-EOF mode is the default for menu
files) - change the Ctrl-AZ sequence from "premature end-of-file" to instead
send an actual Ctrl-Z character (similiar to Ctrl-AA, Ctrl-AL, etc.). This
changes the long-standing behavior of what Ctrl-AZ does, but since that was
a dubious "feature" that I'm pretty sure nobody used, I'm will to take that
chance. If you need a premature EOF now, just use a regular ole Ctrl-Z
char instead (or even the @eof@ code). Of course the msgscan.asc now has
to change accordingly.

terminal text and attributes with a linked-list. In doing so:
- the save depth is no longer fixed (at 4), but dynamic and unbounded
- the current column position is also saved/restored (bug fix)
- no more copy/pasta from sbbsdefs.h into js_console.cpp
- the JS console.saveline() and restore() methods now return Bool to indicate
  success/failure

Also, some trailing white-space was auto-removed due to local editor settings.

previous commit: don't clear the line counter or call pause() - which will
do nothing - if the console abort flag is set.

("Node X", user alias, etc.) - so removing a lot of the redundancies.
Also, logging the current timed event code and other prefixes in the
event thread log messages - something I've wanted for a while now.
There might be some redundant "Node X" strings, so if you see some funny
looking log message, please let me know.

from the Chat menu would immediately clear the screen and redisplay the
menu after displaying the change in the node's state. This was due to the
enhancement in rev 1.77 of con_out.cpp whereby we no longer increment
lncntr if the first lines displayed after a key-press are blank (who
cares if blank lines scroll off the screen?). That's fine and all, but the
auto-pause check in outchar(FF) would only auto-pause if the line-counter
was greater than *one* (has been this way since forever). So with the
enhancement in 1.77, a single non-blank line displayed after a key-press
was now not enough to trigger the auto-pause ([Hit a Key] prompt).
So I've changed the line-counter trigger value to greater than *zero*,
which means we could have some new excessive auto-pauses, but other places
where auto-pause wasn't working, should again.

One new excessive auto-pause was after the system password was entered at
the SY: prompt, so that fix is included in this commit.

ESC \ or ESC X.  ESC followed by anything from '@' to '_' is an element of
the C1 set, it's just that ESC [ is the most commonly used one.

Use < 4 since APS, DCS, PM and OSC also have their own escape parsing.

Privacy Message, Operating System Command, Start Of String) in outcom.

buffer if full. So now everything that uses outcom (including JS
console.write) now includes a retry. The lower-level non-retry outcom()
was renamed _outcom() (and is used by outcom).
Added new Ctrl-A code: Ctrl-AF - enables the blink attribute, but only
if/when a blink font was activated in the terminal. Lower-case 'f' refers
to the normal-intensity blink-font. Uppercase 'F' refers to the high
intensity blink-font. This allows you to mix fonts in text/menu files
and not have annoying blinking text in non-supporting terminals. This is
the first Ctrl-A code to be case-sensitive.

- this code will print a blank line if the previously printed line was not blank

- When the Ctrl-A code is encountered, the terminal server will output a
  new-line sequence (CRLF), but only if the current column is not the first
  column. This is helpful for text.dat lines where you cannot make assumptions
  about the previously displayed text and you want to insure the cursor is at
  the beginning of a new-line without creating unnecessary blank lines in the
  output.

- If the first lines sent after a key-press are blank lines, don't count them
  in the line-counter (lncntr) - maximize the viewable data before pause.
- Assume tabs chars are expanded to 8-space tab-stops when detecting auto
  line-wrapped output (e.g. when ;LISTing text files with tabs)

how "frequent" the progress meter/percentage displayed is updated.
Most uses of this function are now using a interval of 10 so that fast-running
searches aren't now "slow" due to the progress display.

'J' - Clear to End-of-Screen, for ANSI users sends <ESC>[J, nothing otherwise
'`' - Home Cursor, for ANSI users sends <ESC>[H, form feed otherwise

Introduced a better progress indicator (similar to poll results), using the
backfill() method. 2 new attr.cfg fields allow the progress indicator colors to
be configured separately from poll results (though they default to the same
white on magenta). This new progress indicator is used when loading msg ptrs
and scanning for votes. I will be using it while performing other searches
(e.g. file libraries/dirs) as well.

it displays a string of text and fills the background color up to the
specified percentage fo the string length. I will be using it for displaying
poll results, but it could possibly be used for progress displays and such.
The colors used are configured via the "backfill" and "unfill" attributes in
ctrl/attr.cfg.

"top-of-screen" flag or clear the column counter when in ANSI mode.

was never used. This was intended to be a method for internationalization,
letting the sysop change which key is used as the uiniversal "quit" key.
This commit replaces most of the uses of the hard-coded 'Q' for quit wtih the
3rd charcter in the text.dat YNQP string. Some hard-coded menus still have the
'Q' key hard-coded and will need to be addressed later. The text.h YN index
macro was changed to YNQP and the JS text index variable name will change
as well.

in SCFG->System->Toggle Options.

all exported functions and data types using a 32-bit time_t (time32_t).

sbbs_t::rputs() now:
* Can accept an optional length argument which allows it to output strings
with embedded NULs if desired.
* If a call to outcom() fails, terminates and returns the sent number of chars.
* Performs Telnet IAC escaping when appropriate.
* Checks online value in while() loop.
* No longer output to log if "on local" - event scripts aren't expected to use
this function.
JS console.write() and writeln() now use rputs() instead of putcom() so that
Telnet IAC chars are escaped when necessary and saveline/restoreline will work.
sbbs_t::putcom() now returns the number of chars sent successfully.

in the "save line buffer" so that the SAVELINE/RESTORELINE macros will work
correctly again (redisplay with correct attributes).

argument and buffer and retruns an optimized ANSI sequence to generate
the desired attribute.
console.ansi() method now support this usage as well, so msgutils.js's
attr_to_ansi() should no longer be needed.