camera2: save on external storage

based on the old 4.2 patches and adapted to the new
4.4 camera and the raw feature we have this commit
allows to save the taken pics/videos on external
sdcard

Change-Id: Id75959bc26eb8c95aff30acb2448b8e522da7e6b

Conflicts:
	src/com/android/camera/CameraSettings.java
	src/com/android/camera/ComboPreferences.java
	src/com/android/camera/PhotoMenu.java
	src/com/android/camera/VideoMenu.java
	src/com/android/camera/VideoModule.java