HOVER: Option to disable HOVER-Button in StatusBar [1/2]

If the button is hidden, user can activate Hover in the Settings instead

Change-Id: I76e99da7a83b6a5dd35c2965b311009dfc819085
Merge commit 'refs/changes/04/804/1' of https://review.carbonrom.org/CarbonDev/android_frameworks_base into kk