Automate turning contributor name list into github profile links

[myronmarston]

Quoting @dchelimsky from rspec/rspec.github.io#70:

Lastly, and I realize this is a bit of work (though it could probably be automated), I'd turn the names of all the contributors to links to their github profiles.

I wouldn't want to do this by hand. rspec-dev has the rake task that generates the version stats (including the contributor list) and would be the place to do this if we were going to do it.

Would be a nice-to-have for future releases.