Feature : Volume adjust sound preference 1/2

This patch allows the users to choose if they want the audible tone when adjusting the volume

The new preference is in
Settings | Sound
    Volume adjust sound
        Play sound when adjusting volume with hard keys
The Checkbox is defaulted to ON (1 in defaults.xml)

Look for 2/2 for the Settings, Sound Panel Change

[mikeioannina]: Update for L

Change-Id: I705c23065706317760ba60efc1a71f3ba6082bbd