branched to test adding tinting (r,g,b multipliers) - currently implemented on the Flash target.
implemented rgb tinting for webgl target
Tinting working for Flash and WebGL, now using AnimatedFloat values for tintR,tintG,tintB

- had to edit the MovieSprite LayerAnimator, passing it a reference to the parent MovieSprite so the child layers can be tinted by their parent. There's probably a nicer way of doing that.