add koush's Superuser

...

 On branch rz-42-linaro
 Changes to be committed:
	modified:   Android.mk
	modified:   AndroidManifest.xml
	modified:   proguard.flags
	modified:   res/xml/settings_headers.xml

Change-Id: Icde5c4afc387c272b03ca9dc041ec5b83b602a92