A log module handles logging of requests. It can be used to log
requests by other means then log files, or to disable the builtin
logging for some requests.
The module type constant is MODULE_LOGGER.
int(0..1) log( RequestID id, mapping response )
id is the request information object, response is a mapping
containing the response information that are about to be sent to the
browser. If the log() method returns one the logging will stop, and no
other log modules will be called nor will the internal logging take
place.