(Squashed) Lockscreen Notifications [1/2]

Initial
  My try on making notifications easily accessable from lockscreen.
  Credits to ChameleonOS, I got the notification listener permission and some small other stuff from their ActiveDisplay implementation.

  Lockscreen Notifications allow you to manage all your notifications directly on the lockscreen.

  Features:
  - Pocket mode turn screen on when phone is pulled out of pocket and turn it off when phone gets back in pocket
  - Hide low priority notifications
  - Hide non-clearable notifications
  - Allow dismissing even non-clearable notifications from lockscreen
  - Just turn screen on when there's currently a notification pending
  - Toggle between expanded and normal notification view by longpressing
  - Wake on new notification
  - Configure notification count displayed at once
  - Privacy Mode: disable showing notification content.
  - Blacklist apps - thanks to ChameleonOS for the original implementation and @Der-Schubi for bringing it to lockscreen notifications
  - Show all/dismiss all button

  This should still be considered as beta, even if it seems to work very well for me.

  Overlay setting:
  dynamic width is disabled by default, to enable it for a specific device, add
  <bool name="config_lnDynamicWidth">true</bool>
  to yourdevicetree/overlay/frameworks/base/packages/Keyguard/res/values/config.xml

LN: Some fixes & cleanup
  - Fix bug that the notification is launched when a button on it is pressed
  - Show new notifications first

LN: Fix FC on launching hangouts notification

LN: beautify