Odnoklassniki backend requires authization by POST

[antisvin]

Doesn't work without ACCESS_TOKEN_METHOD = 'POST' in social.backends.odnoklassniki.OdnoklassnikiOAuth2 . This is mentioned in their docs as well (http://apiok.ru/wiki/pages/viewpage.action?pageId=12878032)

[omab]

@antisvin, changed, please test. Thanks!

[antisvin]

Tested, works like a charm. Keep up the good work!