Lots of entity chess set work
Pretty much functional now!  Needs more testing.
Added accessor method AIFactory.getInstance()
persistence & worldEditPlugin fields are now non-static
Use precompiled regexp to match sound names - faster.
auto_teleport_on_join now affects the game creator too
Added new auto_teleport_on_start setting
/chess tp <board-name> now works, if there's no game named <board-name>
Clicking to tp to square now only works if the square is empty
Can now set some entity details e.g. slime size, horse appearance
Modified the "entity" chess set to take advantage of this.
Fixed NPE in piece promotion with entity sets.
Entity pieces faster by default
Slow down villagers a bit, speed up blazes
Modified "entity" piece style again - blaze for black king (enderman has
porting issues in the rain), undead horse for black knight, villager
librarian for white bishop.
Version => 2.4.0