Replaced 'vkontakte' to 'vk.com' in strings, class names, variables, because social network was officially renamed. Also explicitly split oauth backend into the oauth backend and iframe applications backend.
Fixed bug which prevented VK.com backend from picking up first_name and last_name
Renamed vk.com's backend from vkontakte.py to the vk.py
Added a stub to inform about backward-incompatible changes
Documentation update
Add myself to the list of contributors
Merge pull request #675 from uruz/vk

Vkontakte backend update