(defaults to 10 megabytes, "10M").
When SBBSecho starts up, if this minimum amount of free space is not
available in any of the following directories, SBBSecho will display an
error and immediately exit:
- data directory (in SCFG)
- logs directory (in SCFG)
- netmail directory (in SCFG)
- outbound directory (from sbbsecho.ini)
- temp directory
- each linked-node's outbox, if configured

If the sysop runs out of disk space for some reason, at least SBBSecho
won't contribute to the problem.

prompts with the conditional beep enabled only with the '-b' option
(silent by default). Thanks to Nelgin.

with smb_t.status.

not null on failure.

Also, is that some line ending weirdness?  *shrug*

'l' (list messages), 'x' (dump index), 'r' (read msgs), and 'v' (view msgs)
commands by "days old", by specifying a negative number (in days).
(e.g. "smbutil r-30" would read messages posted within the past 30 days).
This was added to test the smb_getmsgidx_by_time() function, but has some
value otherwise I suppose.

userdatdupe() to match the passed login-id (username):
*  This allows more permissive username matching, e.g. if your user name
   is "Analog Kid", you could login with "analogkid", "analog.kid" or
   "analog_kid", which is handy when passing a user name on the command
   line (e.g. to an ssh client) for example.
*  This is the same function used for Telnet logins via exec/login.js

so that the current sub/group and dir/lib short name is displayed as
part of the prompt.

@-codes within them. Previously, only if the entire mnemonic string was
comprised of an @-code would it be expanded, now any @-codes within will expand
as well.

experimental 'U' (View Unread-Only toggle) command. The 'U' command from
the e-mail menu (e.g. email_sec.js) works better than the toggle approach and
is probably all that is needed.
Also, the user number lookup in the User Edit bit is better at finding the
proper user account (e.g. for received netmail).

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.

default location to find !include'd baja (*.inc) files. If you use the '-I'
option, it will override the environment variable setting. For Nelgin.

using SSH: the output from the program (file transfer driver, door game)
would reach the SSH client, but input from the client (or user) would not
reach the external program:
passthru_output_thread() - responsible for SSH input from the client/user
to be sent to a "raw" pass-through socket used by the external program,
had a reversed logic bug added around rev 1.686.
Problem was introduced as part of the cryptlib update/SSH overhaul of
early 2018. Thanks to Thumper @ THEWASTE for the bug report!

the sysop must now enable this feature in SCFG->Networks->FidoNet.
Also, widen the FidoNet configuration menu in SCFG, display more FTN
addresses and the default origin line (part of it, at least) in the menu.

the sysop must now enable this feature in SCFG->Networks->FidoNet.

for DOS programs (part of the USE_DOSEMU patch).

flags set manually in SCFG.

(messages which contain the RESCANNED control line) to downlinks.

Also renamed pkt_to_pkt() to write_to_pkts().

"Conditional jump or move depends on uninitialised value(s)"
Thanks, Nelgin.

If the ctrl/ssl.cert file did not exist, the various TLS/SSL services would
fail to create it and (sometimes) log the "creating SSL context" error.
This problem was introduced with rev 1.30 (Mar-9) and the fix/patch
provided by Deuce via irc. Thanks to Psi-Jack for the bug report.

(previuosly) silently fail - in the sendmail_negotiate() and pop3_thread().
If get_ssl_cert() can return -1 withOUT setting the estr argument to a
non-NULL value, then we could still have silent failures (TBD).

(out of disk space?).

properties to msg_area object. See NMAIL_* in sbbsdefs.js for the bit values.

- finduser() method no longer prints "Unknown user" upon failure (the calling
  script can do this if/when it wants).
- read_mail() method now accepts an optional 3rd argumnet (loadmail_mode)
  which may be used to load *only* un-read mail (for example), see LM_* in
  sbbsdefs.js

Pass the lm_mode as a 4th argument to any readmail mod (if one is installed) -
this correlates with the LM_* mode flag values (0 is normal/usual).

File attachments can also be in a file/####.out directory (e.g. outbound
Internet email attachments), so try deleting from there too when deleting
mail with attachments.

- similar to what we do in netmail() with the WM_NETMAIL flag.
If you call writemsg() without WM_EMAIL set, it tries to use the subnum as an
index into the sub-board array and will crash.

var text = load({}, 'text.js');

(not the absense), so we need to call it twice to find out if there are
any unread messages for the user.

Change the 'Edit Author's user account' command to '!' (for now).

user.dat file open (for read operations only). Writing still opens and
closes the user.dat for each property/field modification.

made their display conditional on mailer-type being set to FLO/BSO.
Added a help menu to the BinkP Settings menu (under Linked Nodes).

more control over SBBS-initiated netmail source/origin addresses.

user choose which address to use as the source address when composing a netmail
message (the default being the most appropriate for the dest zone/net). This
change only works with SBBSecho v3.05 or later.
Some other incremental and safety improvements to sbbs_t::netmail() too.
FTN netmail file attachments needs some more work however (the "FA:" subject
prefix trick) - just remove it?