Don't double-up on #main-outlet when static content is rendered through Ember

Linked Meta post: [Page width size for FAQ](http://meta.discourse.org/t/page-width-size-for-faq/4370)

The alternative is to do `text()` -> HTML, then take the contents of `#main-outlet` and convert them back to a string. Since this is a pretty simple use case I figured regex'ing on the comments was the easier (and perhaps slightly more efficient) approach, even if it is kind of deliberate.