quick camera 1/2

Longpress power key to open reboot dialog then longpress power key again
to open the camera. Disabled on the lockscreen and if the device does not
have a camera.

-VanirAOSP

PS2: make quick cam skip the reboot dialog step in landscape orientation
PS3: remove orientation until forced landscape apps like netflix can override quick cam
PS4: Fix leak in CM code causing dialog != null on dismiss

Change-Id: Ic7abb21b8a3e9a5377e80e65fe364515105a2ccf