Early draft of the ForumStore. Not much to see here yet!
Fixed a race condition in forum creation.
Fixed a race condition in group creation.
Fixed a race condition in forum deletion.
Moved four queries to the query generator.
Renamed StaticTopicStore to MemoryTopicStore.
Renamed StaticUserStore to MemoryUserStore.
SimpleSessionCheck is now pluggable.
We no longer have any raw queries outside mysql.go or the query generator, yay.