Handle play and pause media buttons

Implement feature following this request:

from:	 Björn Hutmacher
date:	 Wed, Aug 13, 2014 at 6:15 AM
subject: Xmp Mod Player for Android bluetooth speaker issue

I've got a bluetooth speaker which has remote control buttons on it. All
of them work as intended in Xmp except for the play/pause button. I've
looked through the log and saw that the speaker sends key codes 126 (pause)
and 127 (play), instead of 85 (play/pause). This doesn't seem to be
recognized by the app. Could you please add support for it so users can
use such buttons?

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Update version number and changelog

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Add missing subsong button drawables

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>