Use ToTempSummon() in a case instead of a C style cast.

Use correct Unit::GetCreature() instead of Unit::GetUnit() with casting the object to Creature pointer.
Remove some usless casts.
Fix a possible crash in pyrewood_ambushAI.

TODO: Remove ugly cast macros(like CAST_PLR(), CAST_CRE()) from scripts and use the correct ToX() functions(like ToPlayer(), ToCreature()).

--HG--
branch : trunk

src/scripts/northrend/zuldrak.cpp

@@ -277,7 +277,7 @@ struct npc_gurgthockAI : public ScriptedAI
 
         for(std::list<uint64>::iterator itr = SummonList.begin(); itr != SummonList.end(); ++itr)
         {
-            if (Creature* pTemp = (Creature*)Unit::GetUnit(*m_creature, *itr))
+            if (Creature* pTemp = Unit::GetCreature(*m_creature, *itr))
                 if (pTemp)
                     pTemp->RemoveFromWorld();
         }