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Exploratory installation of Blacklight Advanced Search gem, satisfying #203 

![screen shot 2014-06-05 at 7 36 51 am](https://cloud.githubusercontent.com/assets/1656824/3188887/dbfb67b2-ecbe-11e3-8ff1-2ebfcd3cdb28.png)

Started porting over integration tests after meeting with @ndushay but realized we probably need to meet as a group to discuss further.
Yeah, I'm struggling to find the right name.  I was thinking along the lines of `active_class_for_current_page` or `current_page_active_class` although I can see downsides to both of those as well.