Create page for mozilla.

This page should not be empty. I created a simple site presenting
mozilla activity on Github. It's good supplement instead of a 404 error.

Features:
* __members__
* __projects__

![Example](https://dl.dropboxusercontent.com/u/103345209/Screenshot%202014-06-17%2001.46.13.png)

Review it. @potch @ozten @zaach @tofumatt
Yep, but often https://github.com/mozilla/sweet.js/blob/gh-pages/_layouts/default.html#L117