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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.
This confused me a bit at first.  The method name appears to be asking the question (is the current page active) although that's really what `current_page?` does.

It appears (unless I'm mistaken) that this method is returning a (css) class to be used if the current page is active. Can we change the name of this method to better reflect that?