CodeSearch: Change endpoint from http to https.

@MrChrisW @jdorweiler It looks like it wasn't working because the HTTP endpoint was redirecting to the HTTPS endpoint, and we don't have anything configured to handle that. Switching to HTTPS fixes the problem.

![screen shot 2015-01-01 at 1 53 55 pm](https://cloud.githubusercontent.com/assets/81969/5593029/b036479c-91bd-11e4-8cdf-21fa5517f13a.png)