Changed ExifToLatLngConverter to ExifToLatLngParser due to AS bug of not being able to add files to git if originally say no when prompted. Split out from ImageHelper. ImageHelper now only deals with images given a filepath (via static methods) - no more responsibility for creating/deleting files.

 Review has ImageChooser that deals with finding all Intents that can respond to getting an image, and deals with creatin, saving and deleting image files if Intents cancelled or return null.