Allow Animation to generate its own Renderables.

OpenRA.Mods.RA/Effects/Explosion.cs

@@ -31,7 +31,7 @@ namespace OpenRA.Mods.RA.Effects
 
 		public IEnumerable<IRenderable> Render(WorldRenderer wr)
 		{
-			yield return new SpriteRenderable(anim.Image, pos, 0, wr.Palette("effect"), 1f);
+			return anim.Render(pos, wr.Palette("effect"));
 		}
 	}
 }