Add translation for subregions of Russian Federation to russian language

Hello, I've translated Russian subject names to russian :smiley: 

Russian names are taken from [Wikipedia article with list of all Russian Federation subregions](http://ru.wikipedia.org/wiki/%D0%9A%D0%BE%D0%B4%D1%8B_%D1%81%D1%83%D0%B1%D1%8A%D0%B5%D0%BA%D1%82%D0%BE%D0%B2_%D0%A0%D0%BE%D1%81%D1%81%D0%B8%D0%B9%D1%81%D0%BA%D0%BE%D0%B9_%D0%A4%D0%B5%D0%B4%D0%B5%D1%80%D0%B0%D1%86%D0%B8%D0%B8).

P.S> Thanks for the nice gem! :+1: