Moving code hosting to GitHub

[David Trowbridge]

Because SVN is old news, we're moving django-evolution to GitHub. There were a couple unofficial clones there already, but we now have an official one that people can fork to their hearts content.

Christian will update the google code page to point there soon, but for now, if you want to clone the repository, it's at https://github.com/beanbaginc/django-evolution

-David