AI should wait for a certain number of turns before looking for gold or building rooms instead of time
Added a replay menu

Please note that this feature is pretty experimental as it relies on timestamps where the server/client relies on message synchronization
But because the client in replay is the most simple, timings should not be a too big problem
Moreover, the replays takes there information from the level map. That means that if the level file is modified, there can be weird issues (same as wrong synchronization between server and client level)

But IMHO, it is a cool feature and it can help a lot debugging weird issues (like ghost tiles) so it is worth the price ^^

Later, it would be nice to have options to:
- Save only last replay (should be default)
- Do not save any replay
- Save all replay (like it is currently done)
Because on long games, replay could be quite big (for 10 minutes, it was more or less 10Mb from what I've seen)

Also note that every server related events won't be available (like the creature stats info unless it has been displayed at the same time).
Moreover, because everything is timestamped, if you pause the game, you will see it pause during replay ^^
Removed NullAI, AIFactory and AIWrapper. Renamed Keeper2AI to KeeperAI
Most of the AIWrapper has been moved to BaseAI (to be shared between AIs)
The factory has been moved to the AIManager
fixes #328
Fixed bugs within dormitory:
- Beds were misplaced
- When some tiles were destroyed, some beds (bigger that 1x1) were not removed
- When some tiles were destroyed, some beds were removed when they should not due to wrong activespot management (also true for treasury)
- Merged some functions that were splitted during first attempts to fix multiplayer (deprecated by later commits)

fixes #243
fixes #326
Forced to stop handling messages when the mode changes while launching a replay to allow the new mode to take place before related messages are processed (fixes the wrong mode assertion while launching a replay)
+ Added game time display when pressing F11
fixed wrong path for include file thanks to @akien-mga
Fixed the floodfill bug not allowing kobolds to dig gold surrounded by water in stone keep siege
fixes #289
Fixed error while launching 2 consecutive replays + compilation warning
Merge pull request #330 from hwoarangmy/development

Added a replay menu