- scriptified the remains of APowerup.

- ensure that actor defaults contain a valid virtual table and class pointer so that they can actually use virtual and class-dependent method functions. This is needed for retrieving script variables from them.

src/p_mobj.cpp

@@ -3954,7 +3954,7 @@ void AActor::Tick ()
 		// by the order in the inventory, not the order in the thinker table
 		while (item != NULL && item->Owner == this)
 		{
-			item->CallDoEffect();
+			item->DoEffect();
 			item = item->Inventory;
 		}