[suggestion] Collision Box Plugin

With all this talk of mobile I thought I would add a request. Currently I tend to use transparent sprites to work as collision boxes. However with transparency causes a hit on rendering for mobile. i thought it would be best to include a proper collision box.

Also with the collision box.

* The box should be designed as connected to an image point. As it is now I need to unpin and pin when mirroring

* Shift to image points on different frames.

* remove box if the sprite frame doesn't have the image point.

* collision box should not trigger to designated UID sprite(ie owner)

While it's true that transparent sprites are still rendered, if you make a sprite invisible it isn't rendered at all.

Thanks. such a simple solution the transparency part :) that's a great piece of advice. so simple and overlooked :D

Doesn't solve the mirroring annoyance though :| oh well. it's just convenience.