Merge pull request #282 from MIT-Mobile/3.6/dev-intrepid-adolce

Add self-guided tour stop details view
Move annotation and callout view files into separate subgroup
Set up basic collection view for main stop selection in footer
Implement collection view paging via custom layout
Implement infinite scrolling with custom UICollectionView
Set up "Near Here" collection view
Add numbering of stops in collection view cells
Polish collection view cell layout