* Align touch and tracking system in ASControlNode to UIControl
Currently the touch and tracking system of ASControlNode does not align with the system of UIControl. ASControlNode does not even consider `beginTrackingWithTouch:withEvent:` or `continueTrackingWithTouch:withEvent:`.
This commit will change the ASControlNode logic around touch event handling and tracking to align with UIControl.
* Add assertion for layer backed nodes that would like to add an action target for a control event
* Adress comments