First pass at announcement order editing and viewing

Added [Angular](http://angularjs.org), [Bower](http://bower.io/), relevant related components and code to power a JS-heavy editor. Also added the viewer (also powered by angular) and set it to poll naively for now.

Relevant interesting files:
* `app/assets/javascripts/application.js` Now has bower-managed javascript dependencies
* `app/assets/javascripts/ballyhoo.coffee` is the root of the angular application
* Some new views in `app/views/` especially [jbuilder](https://github.com/rails/jbuilder) views to power angular
* `app/views/js_templates/` gets automagically handled by `ApplicationHelper#render_javascript_templates`, magic! ;)

Obviously a lot of new things here but will make our lives easier in the long run.