This fixes the stat() issue on Windows XP/2K3 by allowing sbbs to benefit
from the run-time library updates that Microsoft releases periodically
(like https://www.microsoft.com/en-us/download/details.aspx?id=53840).

For more info on the stat() issue which caused all kinds of sbbs errors
(e.g. creating directories initially, but a lot more):
https://stackoverflow.com/questions/32452777/visual-c-2015-express-stat-not-working-on-windows-xp

Since we are using cryptlib which requires the MSVC runtime DLL anyway
(it is the default build behavior of MSVC), we weren't really gaining
anything from statically linking the CRTL (LIBCMT.LIB). And for some reason,
an up-to-date MSVC2019 still has (links-in) a LIBCMT.LIB file that includes
this stat bug. All the online help resources I found just to seem to suggest
updating the CRTL DLLs (on the target system), with no mention of any fixes
available for the static CRTLs on the build system. But with the no gain
from static linking anyway, I figured it was time to switch to DLL CRTLs.

The debug builds are still statically linking the CRTL for no particular
reason.

And fix Debug build error (/ZI) and warning (/Gm)

(e.g. with ^C).

Most of the copyright years in the source code were misleading (the date of
most recent publish was actually later) and all were unnecessary. I've been
removing copyright years piecemeal, for a long time, but I decided it was time
to just perform a bulk search and (mostly) replace. In some cases, I left
old copyright years on files that either are not used (and soon to be removed)
or obsolete and unlikely to ever be touched again (e.g. Win9x FOSSIL VXD). Some
of the runtime binaries still contain copyright years and those were updated to
2018.

application" error message (when run on XP) and reportedly will allow target
executables to run on non-SEE (pre-Pentium III) CPUs. Seriously, anyone really
running Windows XP on a Pentium II today? I guess it's possible <shrug> and we
really get little benefit from SSE in Synchronet.

I couldn't get Windows 2000 running in Hyper-V, so I guess Windows 2000 is
now officially unsupported by Synchronet (and long unsupported by Microsoft).

Thanks to Android8675 for the bug report and Rushfan for the solution tip.

loop immediately upon socket receive error (e.g. 54, ECONNRESET).

from everything that links with the sbbs library.

Also, use the absolute path to the 3rdp stuff to silence CMake warnings.

New sexpots.ini [modem] keys:
Answer (default: "ATA")
Ring (default: "RING")
ManualAnswer (default: false)

- configurable via [modem] CmdRetry, default value is 2 retries
- drops DTR, delays and the raises DTR before retrying modem commands
Improved log output:
- don't log COM Device value when passed live com handle/descriptor on cmdline
- log COM Device value in modem command/response errors
- more debug-related log output
Fix modem re-initialization time-out (off by one)
- ReInit value of 1 would result in reinit every 2 minutes of inactivity

many minutes of inactivity waiting for a caller (like sbbs2).
(defaullt: 60 minutes, 0 = disabled).

example sexpots.ini in docs/sexpots.txt) - now truncates string values (com dev
name, init strings, etc.) at first white-space char. Bug reported by Netsurge.

(over-riding the default log level of "info").

("^M" to send a carriage return, for example).

HangupAttempts is configurable in the [com] section of the sexpots.ini file.

I will add daemonizing when two conditions are met...
1) Someone confirms that it works.
2) Someone confirms that it works on Linux.

I'm particularily worried about the comWriteByte() and comWriteString()
error handling (or lack thereof)... Especially in modem_send()

Also, I think the timeout mechanism should be in comReadByte() itself
so we don't need to use while(1) { poll(); yield(); } loops.

I assume that Win32 supports read timeouts... if not, a single loop and
only for Win32 would be preferable to having it multiple places.

the key doesn't exist.

over-riding sexpots.ini key values with default values if a secondary .ini file
is specified on the command-line.

Converts 'P' and 'O' CID responses to "Private" and "Out-of-area".