text: Title: Rename `after_import_instance()` method for clarity
  Body: The `after_import_instance()` is a misnomer because it is called after the instances is loaded (or created) and not after it is imported.  Existing clients rely on this method so it would have to be deprecated correctly rather than simply renaming.
  
  It would also be a good idea to pass the row in as a kwarg so that that users can use row data if they need to.
  