l10n: Russian localization started

[DJm00n]

All work will be done in git-po-ru Transifex project and then uploaded into my Github clone.
Sorry but Transifex creates useless header in translated po:

# SOME DESCRIPTIVE TITLE.
# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
# This file is distributed under the same license as the PACKAGE package.

I hope this is not a problem.

[jiangxin]

First I want to say sorry for my late to give feedback.

It is great to have another popular language support for Git, and do it with Transifex is OK.
But before I merge, your contributions should pass some basic tests, such as format
checkings on commit message, and syntax checking on ".po" file. I found there were
no s-o-b (Singed-off-by) line in your commits, and you can add it using "commit -s".

I will create a WIP (Working-in-progress) branch for ru, and when you finish the whole
translation, you should squash all the trivial commits into a big one, and send new
pull request.