Updated to use fxos-mvc and fxos-camera web component.

I was actually hoping that this entire file wouldn't become a "module" and would just be attached to `window`. I just need to be able to include a <script> tag in the <head> that registers this custom element. Right now, since everything gets turned into a module, I can't create a <fxos-camera> element unless I first `import` this module.