The difficulty with a user-readable ``type`` name is that I don't think RapidSMS polls stores one. There are the single letter codes and the labels (which are human readable but not intended for parsing by machine).

For the ``response_type`` there are only two possible values, so it's possible to translate the two single letter codes to anything we like, but at the cost of not being consistent with.

Perhaps we should ignore the extended ``type`` names and simply label them ``other`` in the API? We can extend the API list as needed later?