[2/2] Settings: Optional statusbar battery icons

Mix of commits from
PA(Anu6is): https://github.com/AOSPA/android_packages_apps_Settings/commit/9d12771bf92365367abf9f864336636361280e46
Slim(kufikugel) https://github.com/SlimRoms/frameworks_base/commit/09052553399741defd000b8886e39bc8beb9afd7