Android/NEWT MouseEvent: Fix Delivery of MultiTouch PRESSED/RELEASE; …

…Fix Detection/Processing of 2-Finger-Scroll Gesture ; GearsES2: Add NEWT based 'zoom' gesture detection.

- Fix Delivery of MultiTouch PRESSED/RELEASE
  Adopting MouseEvent changes of commit 18cb572

- Fix Detection/Processing of 2-Finger-Scroll Gesture

  Dropping utilization of Android's GestureDetector and implementing our own,
  which turns out to simplify keeping track of states.

  Our gesture detection works well w/ user NEWT based gesture detection (-> See GearsES2 zoom and rotate),
  using following criteria related to Android parameter:
     - ScaledDoubleTapSlop:
        - Max 2 finger distance

     - ScaledTouchSlop:
        - Min. movement w/ 2 pointer withing ScaledDoubleTapSlop starting 'scroll' mode
        - Max. change of finger distance in respect to initiating 2-finger distance (2x ScaledTouchSlop)
        - Max. distance growth in respect to initiating 2-finger distance.

- GearsES2: Add NEWT based 'zoom' gesture detection.