Update All The Things

* IG-38 #resolve #close Completed token-based auth for the splash site.
* IG-39 #comment Template is finished, but the copy needs to be updated.
* Added ARIA support to AngularJS.
* IG-40 #comment Began building the invitations portion of the admin site.
* Renamed Angular files and components in keeping with Google's
  recommended best practices.
* Updated Gemfile.
Update All The Things
Shrinky-Dink

* Subset all fonts, dramatically reducing their overall size.
* Refactor routing error handler.
I Brake for Errors

* Add Airbrake exception monitoring to the backend Rails and frontend
    Angular apps.
* Switch back to Rails master.
* Restore deployment notifications in HipChat.
Auth Ready

* Completed authentication module; site is now closed to anyone without
    an invitation token.
* IG-40 #resolve #close Basic admin interface allows us to invite users.
* IG-39 #resolve #close Template is finished; copy may be fine?
* Wrote all JavaScripts in JavaScript. CoffeeScript, we hardly knew ye.
* Added CircleCI configuration.
Merge branch 'feature/angular-auth' into develop

* feature/angular-auth:
  Auth Ready
  I Brake for Errors
  Shrinky-Dink
  Update All The Things
  Update All The Things
CircleCI Fixes

* Remove redundant package.json.
* Update Gemfile.
* Update Teaspoon config/shim.