Settings: Bringup expanded desktop and implement per-user configuration.

Change-Id: Ib673d278d23423fe6885c73f1eb3dd858633e5b6

Conflicts:
	res/values/cm_strings.xml

	new file:   res/drawable-mdpi/checkmark.png
	new file:   res/drawable-xhdpi/checkmark.png
	new file:   res/drawable/expanded_close_bg.xml
	new file:   res/drawable/expanded_item_background.xml
	new file:   res/drawable/fab.xml
	new file:   res/layout/expanded_desktop.xml
	new file:   res/layout/expanded_item.xml
	new file:   res/menu/expanded_desktop.xml
	new file:   res/menu/expanded_desktop_chooser.xml
	new file:   res/values/cm_colors.xml
	modified:   res/values/cm_dimens.xml
	modified:   res/values/cm_strings.xml
	modified:   res/xml/display_settings.xml
	new file:   src/com/android/settings/applications/ExpandedDesktopPreferenceFragment.java