Backend updates and a bugfix

Today I found that a MySQL query I have used for months could be replaced with a much faster query (maybe 15 times faster). So there should be a great performance increase for the whole system. Also now all shoutbox pages are compressed before they are sent to your browser (if your browser support it) so the latter will specially speed up for people with slow connections.

I have also fixed a bug in the login system that caused the auto-login after register session to be invalid.