Gesture updates:

- User can now define unlock and sound toggle gestures.
- Lockscreen tabs can now be fully disabled, but ONLY if there is
  some other method of unlocking the device enabled.  This includes:
  Trackball unlock, menu key unlock, and gesture unlock.
- Changed default gesture sensitivity to 3
- Users are prevented from creating gestures that cannot be
  reproduced on the lock screen (namely vertical single-leg swipes)

Change-Id: I553ab3c9828d0478fb46821f2c36e87e865d7680