Swap volume buttons when the screen is rotated by 90 or 180 degrees

Change to default behaviour not configurable due that it is now
more natural

Change-Id: I323b647066e8c73fac60067141d1add7b2f9962d
AudioManager: make swap volume buttons RTL aware

The layout of the volume panel is already RTL aware...the problem is
if it is in landscape and the buttons are swapped they go into opposite
direction then the volume panel.

So this swap should only happen on LTR languages and RTL should be left
like it is.

So both LTR and RTL have it logical.

Change-Id: Ie5fbe3085b40ad35814f53ed19736d7800dad78e