Add safe headset volume settings
Option to use volume keys to control media volume anytime [2/2]
The volume keys control the Media volume rather than the Ringer
hence removing the issue of accidentaly changing the Ringer volume.

Credits to Pawitp and mnm9994u
Native battery, double-tap to sleep, status bar brightness control
'private SwitchPreference mVolumeKeysControlMedia' forgotten
Fixes 'n stuff
More fixes 'n stuff
Apparently I was still stuck in the past with Android KitKat