[svn] Send AttackStart package when update visibility.

Update DoMeleeAttackIfReady to support dual wield.
Show player modelid2 instead id3 of triggers. This should fix the bug that gameobject::castspell summon a human model.
Remove the correct flag to make creature attackable. This should fix the bug that Illidan and Magtheridon are unattackable.
Add NullCreatureAI for trinityscript.
Fix channeler's soul transfer.
Some update of black temple scripts.

--HG--
branch : trunk

src/game/GameObject.cpp

@@ -1282,4 +1282,6 @@ void GameObject::CastSpell(Unit* target, uint32 spell)
         trigger->setFaction(14);
         trigger->CastSpell(target, spell, true);
     }
+    //trigger->setDeathState(JUST_DIED);
+    //trigger->RemoveCorpse();
 }