SlimActions: add new actions and cleanup

A bit cleanup.

As well add 4 actions:

- camera intent
- play/pause music
- next music track
- prev music track
- wake up device

As well check for system ready on the other audio actions which are already present.

ToDo: One of the rare classes which are very bad documented. We need to add code comments
ASAP

Change-Id: I73bcfb6c60454de4d8494dfd846deee770022335
Merge remote-tracking branch 'original/kk4.4' into kk4.4

Conflicts:
	core/java/com/android/internal/util/slim/ButtonsConstants.java
Revert "okay this was the last derp."

This reverts commit 64fd1824ef6d6e8c3cd20556a0145771bb1997bc.
Revert "WHY??"

This reverts commit 4eef710e2a9a140e72767992ff4f67fb46a7a9d8.
Revert "why do i always have to mess something up?"

This reverts commit 6ed0ac2fe025e18851bf83f0c269a7ac3850081d.
Revert "(1/2) Add media keys for the navbar."

This reverts commit abdce07fb6ba9eb97e39542243112d6bd3cda645.

Conflicts:
	core/java/com/android/internal/util/slim/ButtonsConstants.java