Core/AreaTriggers: Implementation for sever side area triggers

- Spawn GridLoader to spawn area triggers correctly now
- Removed SAI completely
- Removed remnants of smart scripts. Created different issue for it
- Calling InitDbPhaseShift and not InDbPhaseShift
- changed SpawnId to uint64 rather than uint32
- not using CellGuidSet typedef as to not include ObjectMgr.h in the header

src/server/game/Maps/Map.cpp

@@ -16,6 +16,7 @@
  */
 
 #include "Map.h"
+#include "AreaTriggerDataStore.h"
 #include "Battleground.h"
 #include "CellImpl.h"
 #include "CharacterPackets.h"