Added github url support

Info on pages for:
- Users
- Repos
- Issues
- Commits

![screenshot 2014-06-25 at 4 20 58 am](https://cloud.githubusercontent.com/assets/990370/3382927/596a4d66-fc42-11e3-90de-925779ab8fcc.png)

See: https://github.com/euank/EuIrcBot/issues/4