We don't have a lot to do here, but at least make sure that the logdir is specified and exists.
writeAudit( user, category, message) :
Writes an audit log entry to the audit log file. These audits are semantic logs; they don't record every single modification in the database, but provide a logical "who did what" overview. The exact modification SQL statements are logged automatically with writeSQLAudit() instead. The log file path is configurable in _config.php.
persistent identifier of the user who triggered the action
type of modification, from the fixed vocabulary: "NEW", "OWN", "MOD", "DEL"
message to log into the audit log
TRUE if successful. Will terminate script execution on failure.