[WIP] Tightening up the visual design.

Now includes all files 

* Updates header and navigation to match those in the operator dashboard mocks.
* Uses form styles from style guide
* Matches preview to match the preview in the operator dashboard mocks.
* Strips away UI wherever possible, especially in the app selector, which was needlessly complex for selection of a single app.

Video: http://chuck.mn/0u3X3n422U3h
I am generally against id selectors since overriding them is a bitch and by very definition are not reusable. On this stylesheet though - not sure it matters much.