A few refinements

Hi Robert,

Great job working out how to get around the long press gesture recognizer problem in 1.3.1! I hope this doesn't prove too fragile in the future - it could be that the framework starts to rely on the GMSBlockingGestureRecognizer being present at some point, although for now, that object appears not to have any delegate set on it.

I made a few other refinements for your consideration:

1) Moved the maps API private key back into a separate file that is included in .gitignore - this seems to be the safest way to avoid inadvertently publishing a private key to a public repository
2) Refactored the initWithMapView:delegate: method to avoid referencing self
3) Added a new delegate method mapView:didCancelDraggingMarker: - seems better than sending the didEndDraggingMarker: message if the marker was not actually moved
4) Added new properties on GMDraggableMarkerManager to allow class users to configure the marker animation characteristics

Cheers,

Stephen