basic sketch of an open source landing page

Even though we don't have a ton of open-source stuff, we do have some stuff and we do use it, so seems logical to hype it on a page, if for no other reason that candidates and other curios can see what's up.

This design just copies the team one and sucks, but maybe it'll get the juices flowing.

* Would be nice to generate this somehow from our gemspecs or actual repos, but I don't know how to do that with Jekyll.
* Needs more imagery/color.  I really love Square's http://square.github.io/
* Do we show our forks of various things, too?

![stitch_fix_technology](https://cloud.githubusercontent.com/assets/22282/4485583/8f1dc8fa-49ce-11e4-8bff-b59a510a0d18.png)