Settings: Advanced low battery indicator options (2/2) - Slim

    Based on a idea I saw on Liquid and from CR3C0 (thanks guys) which we
    modified to an extended version

    This commit introduces following new SlimBean modes to indicate low battery

         * 0 = show dialog + play sound (default)
         * 1 = fire notification + play sound
         * 2 = show dialog only
         * 3 = fire notification only
         * 4 = play sound only
         * 5 = none

    Due that notification is a unique SlimBean feature some words on it. Notification
    behaviour is the same as Pop-up. User can dismiss it manually or it is
    dismissed automatically if charger is connected. Also you user get a
    status bar ticker message about the notification and notification is always
    on first place of list. And last if vibration is enabled
    notification vibrates.

    cheers

    Change-Id: Ia8fa8c420e6ef334266a7734fb080026a8396340