Fixup back url in commit status

This is fix for back url in commit status:

![2014-02-13 13-08-29 by floatdrop pull request 6 project-stubyandex-environment](https://f.cloud.github.com/assets/365089/2157561/c92f777e-947e-11e3-88f5-bcc81945f7c4.png)