Updated gh-pages branch with a new index.html created from DOCS.rst

I updated the index.html file so that there is some documentation. If you update the link in the project description to point to http://chrisglass.github.com/django_polymorphic.

I am not sure if this pull request will actually trigger the gh-pages to be "buillt" 

https://help.github.com/articles/creating-project-pages-manually