Toggle: Music Toggle

A port from Slim and CyanogenMod.

Kudos to them. :)

Conflicts:
	packages/SystemUI/res/values/strings.xml
	packages/SystemUI/res/values/strings_toggles.xml
	packages/SystemUI/src/com/android/systemui/statusbar/toggles/ToggleManager.java

Change-Id: I0d9b7b43ffd54cfe8fe6bc8ec40f16db798fb38d