ENYO-42: [Garnet] drag event occurs when multi touch

### Issue: 
Gesture (drag) occurs when two fingers touch simultaneously.
Drag left to right is a gesture for finishing the app on all W2 apps, so it causes an unintentional App exit.

### Fix: 
"identifier" is the property in the touch event which identifies the finger. Store the identifier value which generated the starting touch, and compare it to the event identifier in the touchmove event. Do not generate an enyo move event if the identifier values  do not match, i.e. if they came from different fingers.


Enyo-DCO-1.1-Signed-off-by: Krishna Rangarajan <krishna.rangarajan@lge.com>