WIP: add a change bar based on content status

instead of special-casing `draft` and `publishing` add a changebar (and labels) if a status is set (publishing is blue and draft is yellow). This also simplifies the logic for the case when content is in the `publishing` state.

Screenshot (draft):
![image](https://cloud.githubusercontent.com/assets/253202/2849784/bcafa1d6-d0e7-11e3-8638-e776aef2f488.png)

TODO:

- [ ] make aloha editable not bleed into the changebar
- [ ] add "draft" labels next to the input boxes (they are hidden because of `editable.coffee`