Add "Turn WiFi off" action to "Open networks" notification

Forward ported to kitkat

Squashed:
add "Turn Wi-Fi off" action to the "open networks available"
notification
add missing xhdpi turn wifi off image
WiFi open network notification: fix potential crash

Change-Id: Id1fd4f50755c5172cdc557fc27e2298290edecef
Signed-off-by: Roman Birg <roman@cyngn.com>
Merge remote-tracking branch 'github/cm-11.0' into cm-11.0