Settings: Add preference for EdgeGesture service.

Update: Default to true

Change-Id: I0325b0a9aa6eb943b48483aebe151726a2c64ac4
Clarify Notification PG perm

Blocking notifications also blocks toast messages.

Change-Id: Ib75184db20e38be394de4d6bc3ff136de0f97def
Merge branch 'cm-11.0' of github.com:CyanogenMod/android_packages_apps_Settings into cm-11.0

Merged changes from upstream