add "Turn Wi-Fi off" action to the "open networks available" notification

Signed-off-by: Roman Birg <romanbirg@gmail.com>

Conflicts:
	core/res/res/values/strings.xml
	services/java/com/android/server/WifiService.java

PS2: Adapt to 4.3 changes
PS3: Adapt more to 4.3

Change-Id: Idaed26320a2ff2e6ada448fa6deb95a76d2b86d2