Hardware testing app

This app should integrates several hardware tests like:
LCD colors, Vibrator, Physical buttons, Touch screen and etc.
Please check https://etherpad.mozilla.org/gaia-manual-test-items for the complete list.

The current implementation is based on the UITest in gaia/test_apps.

Link to bugzilla https://bugzilla.mozilla.org/show_bug.cgi?id=913385