* Updated config doc comments.
* Check undefined without typeof. Discussion: https://stackoverflow.com/a/22053469/187883
* Use transparent bg color by default if alpha is true.
* Set bg color on parent to avoid flash.
* render->create (so it doesn't seem like it's about drawing).
* Sorted members.
* Use addEventListener, else only the last player event handler is used.
* Set the initial animation when loaded, not whenever track 0 is empty.
* If an animation is not specified, play an empty animation.
* If an animation is set in success(), don't set any animation.
* Don't clearTracks in setAnimation, don't use AnimationState in calculateAnimationViewport -- those prevent mixing.
* setAnimation returns the TrackEntry.
* Added addAnimation and setViewport.
* Expose play() and pause().
* Keep control bones inside the canvas.
* LoadingScreen scales down.
* Set minimal CSS so no external CSS is needed when !showControls.
* Use screen instead of world coordinates for control bone hit detection, so it works at any size.
* Choose closest control bone instead of last.
