Create groundwork for cluster stats page.

- Create stats.hbs (markup for the stats page)
- Create stats.js (currently contains working non-ember code and broken ember code)
- Add new route in router.js
- New require command in app.js
- New (currently blank) nav item in application.hbs
- New .hbs file listed in rebar.config
- New JS file imported in index.dtl
- Add some basic styles.