Option to toggle torch using power button (1/2)

- Allows user to enable torch by holding the power
  button while the screen is off. When the power
  button is released, the torch is disabled.

Change-Id: I541a823dc4e17b8c727919cdfaa96904f9a3d996

Conflicts:

	core/java/android/provider/Settings.java
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java