Add support for Western Balochi (bgn)

As requested on
https://translatewiki.net/wiki/Thread:User_talk:Nemo_bis/Balochi_language%28_%D8%A8%D9%84%D9%88%DA%86%DB%8C_%29

Change-Id: Idaeb7cecb982eea5e062a56f2ce3b82532c45a34