Clean up quick settings tile code.

- Fix up coding style
- Add copyright headers
- Fix some multi-user bugs
- Streamline code

Conflicts:
	packages/SystemUI/src/com/android/systemui/quicksettings/GPSTile.java
	packages/SystemUI/src/com/android/systemui/quicksettings/HeadsUpTile.java
	packages/SystemUI/src/com/android/systemui/quicksettings/MobileNetworkTile.java