Revert "Revert "Revert "Proximity on wake"""

This reverts commit 6b1d573124cb6369e5b83aa0239a9bd87681c770.

Conflicts:
	res/xml/display_settings.xml
Settings: Add proximity wake option

Ports and combines:

http://review.cyanogenmod.org/#/c/66658/
Settings : Add preference for proximity wake

http://review.cyanogenmod.org/#/c/69347/
Proximity Wake-Up : adjust strings

http://review.cyanogenmod.org/#/c/69803/
Settings : Make proximity opt-in

Change-Id: Iea0853eccf764438c7aaac76afd13c364fcea0ec

Conflicts:
	res/values/cm_strings.xml
	res/xml/display_settings.xml
	src/com/android/settings/DisplaySettings.java