Core/Players: Don't set instanceId to 0 when player is on transport during loading, there CAN be transports inside instances

Core/Scripts: Added waypoint id to OnRelocate transport hook
Core/Scripts: Make use of ZoneScript::GetGameObjectEntry at gameobject creation (makes it possible to override gameobject entries in instances)
Core/Transports: Call InstanceScript::EventInform for transport events
Core/Transports: Use guid from db for transports, not just its entry - adds partial support for instancing them (still cannot use transports table for it, but can spawn manually now)
Scripts/Icecrown Citadel: Fixed crash in Deathbringer Saurfang when event is started by more than one person (can't do this anymore)

Closes isssue #3749.

--HG--
branch : trunk

src/server/game/Instances/InstanceScript.h

@@ -146,8 +146,8 @@ class InstanceScript : public ZoneScript
         virtual void OnPlayerEnter(Player *) {}
 
         //Handle open / close objects
-        //use HandleGameObject(NULL,boolen,GO); in OnObjectCreate in instance scripts
-        //use HandleGameObject(GUID,boolen,NULL); in any other script
+        //use HandleGameObject(0, boolen, GO); in OnObjectCreate in instance scripts
+        //use HandleGameObject(GUID, boolen, NULL); in any other script
         void HandleGameObject(uint64 GUID, bool open, GameObject *go = NULL);
 
         //change active state of doors or buttons