Backbone.js style docs

Closed #230, so I could reopen the same pull request here with the correct branch.  The docs are pretty solid now imo.  I would say let's get them in master, so people can start working on them there, as opposed to in the README.md.  The only major thing that needs to be changed, is we need to link to the development and production versions of Backbone-relational.js on the main page.  Is there standard location that I can link to?  I couldn't find one.

You can see the docs in action [here](http://jayd3e.github.com/Backbone-relational).