Reports promises don't log to Windows event log

Messages generated by reports promises do not show up in the Windows event log - any other message emitted through the logging subsystem does.

Reports promises don't go through the logging subsystem - @verify_reports.c:ReportToLog@ uses @printf@ and @syslog@ (except on Windows) to avoid reports messages being prefixed with timestamp and stack path.

Instead of calling @syslog()@, the function needs to call @LogToSystemLog@ with @LOG_LEVEL_NOTICE@. @LogToSystemLog@ is a static function in @logging.c@, and is then specialised on Windows to write to the event log.