Settings: Bring back app ops

Google didn't expose app ops yet, but we want to.  Places the app ops fragment
under the System header in settings

Thanks @BigBrother1984 for the drawables

ps2: fix indents
ps3: really fix indents
ps4: fix parentActivity key name

Change-Id: I09ec8c0b6d3b681f6b008d140a93f8112814228a
Signed-off-by: Evan Anderson <evan1124@gmail.com>

Conflicts:
	res/xml/slim_advanced_settings.xml