Fix script (and crash in) npc_scarlet_miner_cart

--HG--
branch : trunk

src/server/scripts/EasternKingdoms/ScarletEnclave/chapter1.cpp

@@ -877,7 +877,7 @@ class npc_scarlet_miner_cart : public CreatureScript
 public:
     npc_scarlet_miner_cart() : CreatureScript("npc_scarlet_miner_cart") { }
 
-    CreatureAI* GetAI(Creature *_Creature)
+    CreatureAI* GetAI(Creature *_Creature) const
     {
         return new npc_scarlet_miner_cartAI(_Creature);
     }