Vendor and update Backbone to 1.0.0.

- Remove backbone-rails gem in favor of vendoring those libs directly.
  - Add Backbone 1.0.0
  - Add underscore 1.4.4
  - Add json2 lib
  - Add make method to base cartilage view
    (removed from backbone after 0.9.2)
  - Automatically call stopListening (available now in 1.0.0) on the view and
    use the Backbone remove function to tear down the view
- Tighten bootstrap lib to exact version as even minor revisions can cause unwanted style changes
- Remove padding from h1 for cartilage page-header