Patch for LOG4NET-38 EventLogAppender: Add support for setting the Category on Event Log messages.

[Isaac Devine]

Hi all,

Sorry I don't what your process is here, so I thought I would post to
the dev-list to please review my patch for issue 38 (url below):

https://issues.apache.org/jira/browse/LOG4NET-38

Let me know what needs fixing :-)

Thanks,

Isaac