Make AudioService aware of device orientation changes

If the "ro.audio.monitorOrientation" system property is
 defined and true, monitor device configuration changes
 and see if the device orientation changed. If it did,
 set the "orientation" audio system parameter to one
 of "landscape", "portrait", "square" or "undefined".
Set orientation when starting AudioService, and
 when media server restarts.

Change-Id: Idce548f93abf3aab30149e5952daaa7051630232