Marker attaching

Please test the marker attaching / detaching functionality. I made a minor data API change, so please restart apache on vagrant after you pull. This will need another layer of re-factoring when the infoBubble functionality is refactored to the model level.
This is an opinion thing, but it feels like the logic for acting on whether or not an intersection is occurring shouldn't be in the checkIntersection() method itself.  It might also help to abstract this out in case we run into a use case for intersection that isn't attaching elements to markers