Replace Google search with an in-house built search

In order to launch quickly, we ended up using Google Custom Search for v1.

This is going to be changed to an in-house search. Google's contextual matching is obviously great, but it'll be replaced for three reasons:

• Newer content won't show up instantly until Google re-indexes.
• The look can't be controlled to the degree we'd like.
• Ads. We really hate the ads in G's custom search.