Added BBShapeReducer

Adding a pod spec for BBShapeReducer. This pod spec is modified from the original, ShapeReducer. Included in this update are updates to use ARC as well as some custom init methods to make usage easier. I've also included a dependency on CoreLocation to allow usage of CLLocation objects to create the Shape to be reduced. This reducer can be used on UIMapView as well as Google Maps SDK, GMSMapView.