Disable safe headset volume warning

In some countries, regulations require that a warning be displayed
when the media volume is being raised above recommended level while
using a headset. As this is regulation we don't simply remove the
warning, but instead give the user the option to disable it.

In this implementation, the user is presented with the warning at
least once, at which point they are given the option to disable it
completely (via on-the-spot preference).

PS1: initial commit
PS2: update to reflect changes to https://gerrit.paranoidandroid.co/#/c/3702/
PS3: add new drawable (thanks Arz....finally)

Change-Id: Ib29ddb7f0ed5b1d45ed56d13bd6f7e14d005da79

Conflicts:
	packages/SystemUI/res/values/pa_strings.xml
Spanish translations

Change-Id: I82918b674d0289cb37c8aa83d45c9fe9e456a9c5
VolumePanel: Don't force navigation bar

It always annoyed me that when changing volume while in immersive the navigation bar is shown.
Fix: Correct string reference error

Introduced in https://gerrit.paranoidandroid.co/#/c/3729/

Change-Id: I1e2ce2e4ab0e01a95383b4933044f14f4124bc4c
allow forcing HighEndGfx mode

people have already started fipping the lomRam prop to enable
transparent status bar, this will enable it with fewer
repercussions

Change-Id: Ied6de65276425fa1e7db0bf9da35f1932a355172
Switch quick settings drag to long click

PS2: Remove unused variables
PS3: Fix build

Change-Id: I441b7467127990f387d976132bffc8f881a55095
Fix derp on imports

Change-Id: I3ea2b1767d8788e7ab1ce3972d38b8d1a96477ff