What's new:
- Support for Blacklight 7.
- We've moved the logic for constructing filtered searches into the
SearchBuilder. This requires that we pass an instance of theCanCan::Abilityclass to the search builder. This is done by the controller mixin: https://github.com/projectblacklight/blacklight-access_controls/blob/1c793c820afabc87134f1dffda045c633a580fa2/lib/blacklight/access_controls/catalog.rb#L20