Made Nearby use UICollectionView.

Change-Id: I8aa5a50aa21c26deba4b0de752a4e83668f749fa
Moved angle/distance calc into Nearby controller.
This will vastly simplify doing an 'immersive' presentation
of nearby results.

Also sped things up a bit by dealing with coordinates with
lighter weight struct rather than location object.

Change-Id: I0d08142eb9a4e3085c59b26ca5b329f605246555