Fixed problem causing a warning about the timezone not having been set.   The problem only manifests itself if the timezone hasn't been set by php.ini using date.timezone.   Most php.ini files do this, but some don't.

git-svn-id: http://svn.code.sf.net/p/mrbs/code/mrbs/trunk@2797 25f7e783-145e-4f2d-a9f8-dd7182bfe9c7