Settings: Make Safe headset volume handling user configurable (2 of 2)

Patch set 1  : Initial commit
Patch set 2  : Code cleanup and dedupe

Change-Id: I9d46ba5b8ca5a8b18dcb4856c348c86bc3e70899

Conflicts:
	res/values/strings.xml
	res/xml/sound_settings.xml
	src/com/android/settings/SoundSettings.java

 Author:    DvTonder <david.vantonder@gmail.com>
 On branch jb422
 Changes to be committed:
	modified:   res/values/strings.xml
	modified:   res/xml/sound_settings.xml
	modified:   src/com/android/settings/SoundSettings.java