1096294 - Document the rsyslog log level settings.

Against my better judgement, I've documented another project's config
file in our documentation.

https://bugzilla.redhat.com/show_bug.cgi?id=1096294
Added a comma as per PR review.
Merge pull request #1199 from rbarlow/1096294

1096294 - Document the rsyslog log level settings.