Syslog observer doesn't honor logLevels

Running an application using logLevel in twistd doesn't preserve logLevels 

Reproduce:
1- run #twistd --syslog ...
2- wait for an event with logLevel=WARNING

I expect:
3- the log has syslogSeverity = LOG_WARNING

Instead
4- the syslogSeverity = DEFAULT == LOG_INFO

The following code reproduces the issue.

If you're interested I'll provide a patch.

Thx+Peace,
R.