Core: Add new system for parallelizing client packet processing. Handle WorldSession updates in Map::Update() where we are safe to proceed. Patch by Ambal.

(And clean up tabs and whitespace while rummaging around in there)
Closes issue 5084.

--HG--
branch : trunk

src/server/game/Battlegrounds/Zones/BattlegroundRL.cpp

@@ -55,7 +55,7 @@ void BattlegroundRL::Update(uint32 diff)
             UpdateArenaWorldState();
             CheckArenaAfterTimerConditions();
         }
-    } 
+    }
 }
 
 void BattlegroundRL::StartingEventCloseDoors()