Forum upgrade to SMF

Once again I've updated the forum software - this time to the popular open-source Simple Machines Forum (SMF).

In the process I've also deleted all users who had joined but never posted. Apologies to any genuine users who may be affected by this - it was just too difficult to separate you from all the fake users. If you'd care to join again I promise not to delete you... (until next time!)

As always the upgrade may have some unexpected side-effects so if you notice anything wrong please let me know, either here or privately.

Chris