hide System update setting PreferenceScreen
add few more steps to battery saver trigger values
status bar: native battery percentage
kill app long press back
battery level text: edit settings to match

https://github.com/rascarlo/android_frameworks_base/commit/fcc6ca48f753009f653cbb8b8d84bb6772530b8e
status bar power menu
[settings] long press back to kill configurable timeout (2/2)

1 - 2 seconds (default)
2 - 1,5 seconds
3 - 1 second
4 - 0,5 second

Forward ported from crDroid kk
[Settings]: recents panel clear all button tweaks

- Show or hide recents button
- Place the button in top right or left

@cristianomatos