Settings: Add fast charge QS toggle and other

this commit add
- qs toggle
- interactive reacting with pw toggle
- option stays after reboot
- option is hidden if kernel doesn't support
- code cleanup

Change-Id: I089667e2de01f50032d09e3e9c6eee07dd665c7d

Conflicts:
	res/values/strings.xml
	src/com/android/settings/cyanogenmod/QuickSettings.java
	src/com/android/settings/cyanogenmod/QuickSettingsUtil.java

Conflicts:
	src/com/android/settings/cyanogenmod/QuickSettingsUtil.java