Initial setup for Russian translation of site (ru)

Provides

* most of the locales (in _config.yml),
* the site root page (index.html), and
* the news.rss file.

Also adapts Rakefile.
Add 'examples' directory (ru)
Complete initial files for :ru branch (ru)
Merge pull request #196 from gazay/ru-translation

Complete initial files for :ru branch (ru)
Remove code example for disabled javascript (ru)
Translate about pages (ru)
Merge pull request #197 from gazay/ru-translation-about

Translate about pages (ru)
Fix typo
Translate community pages (ru)
Merge pull request #198 from gazay/ru-translation-community

Translate community pages (ru)
Translate most of the documentation pages (ru)

* index.md
* quickstart
* success-stories
Translate ruby-from-other-languages (ru)
Fix typos in ruby-from-other-languages (ru)
Rename to-ruby-from-c-and-c- to to-ruby-from-c-and-cpp (ru)
Adapt mailing list instructions to GNU Mailman (ru)
Add reference to qtbindings on 'to-ruby-from-java' (ru)
Some fixes from master branch (ru)
Libraries translated (ru)
Merge pull request #311 from gazay/ru-translation-libraries

Ru translation libraries
Merge pull request #310 from gazay/ru-translation

Some fixes from master branch (ru)