[3/3] settings: Change density on the fly

PS2: Rebase
PS3: Rebase
PS4: Rebase
PS5: Fix a small derp

Change-Id: I1d5ac03b1b89500a8e522df768443c89386b0fac

Conflicts:
	AndroidManifest.xml
	res/values/config.xml
	res/values/pac_arrays.xml
	res/values/pac_strings.xml
	src/com/android/settings/DisplaySettings.java