Use Swiftype for search

Apologies for the delay on this!

There was some quirks getting the Swiftype search embed to play nicely that I ultimately fixed with some hacky CSS. Take a look, I won't be offended what you all decide to do with this PR. An alternative to using the search embed is to use some of Swiftype's jQuery plugins ([here](https://github.com/swiftype/swiftype-autocomplete-jquery) and [here](https://github.com/swiftype/swiftype-search-jquery)) to build a custom UI, but that will require a bit more effort.

But! The good news is that you'd have full-text search with this :) Let me know what you think.