Manual touch test: Add gestures.

Add command line options for
- Grabbing gestures
- Suppressing mouse and touch events

Add gesture events to the log.
Add a hierarchy of gesture classes storing the parameters
of finished gestures with drawing functionality and
implement for pan and swipe.

Task-number: QTBUG-46195
Change-Id: I019fe5b60116316a54e11b2c30e1d34f5e72bcf0
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>