Fix various issues with the cgiirc module.

Fix various issues with the cgiirc module.

- Respect the value of <cgiirc:opernotice> when sending snotices
  to operators.
- Write to the log file if opernotice is disabled.
- Log to the correct snomask in all cases. This was caused by an
  oversight when merging insp20 into master.
- Replace the full user mask in log messages with a uuid/ip. The
  WEBIRC command is sent as the first command so there will not be
  a nickname or username at this point.