camera: Add support for sending raw commands

 * Certain camera drivers need magic commands to select special modes
   such as ZSL or HDR. Add support for sending raw commands from
   applications.

Change-Id: I512a765c7a67ffd2877e465cf6493ffc2b3b54ac
Option to use volume keys to control media volume anytime (2/2)

See Settings part for description

Change-Id: I78d26b0bd41f5b58514ae9c68208a8c950396823