Track new stats per invocation of SBBSecho and report during the "signoff"

("Exiting") log message: packets sent, packets imported, bundles sent, and
bundles unpacked.
Signoff log messages is always logged when in "Debug" log level.
Stat groups that are all zeroes are not logged in the "signoff" message.
The inbound, secure_inbound, and outbound directories are now "full pathed",
meaning relative paths become absolute paths, forward-slashes become
backslashes (on Windows), etc. This makes the command-line generated and using
these paths less likely to be incompatible with archive unpackers.
The configured inbound/outbound paths are now logged in "Debug" log level mode.
The optional "outgoing_sem" (used by binkit or tickit.js) is now touched under
more circumstances (e.g. outbound bundle created without exporting any new
mail).
No longer log the "writing" bad areas file debug output.

Area Manager changes:
- Bug-fix: %PASSWORD was setting the wrong key in the [node] section of the
  sbbsecho.ini file (areafix_pwd -> AreafixPwd).
- Enhancement: %PKTPWD command may now be used to change the ndoe's packet
  password. This change takes effect immediately, so additional packets in the
  same session or bundle would need to use the new password. This can be
  changes to take effect the next time SBBSecho is invoked instead, if desired.
- Aliases for AreaMgr commands for commonly supported synonymous commands:
  %PWD -> %PASSWORD
  %COMPRESS -> %COMPRESSION
  %PAUSE -> %PASSIVE
  %RESUME -> %ACTIVE