Replace tuple return value for API user to get both raw and translated data

[lisad]

An API that returns tuples, especially if the tuples contain lists, is hard for API users to use successfully and robustly. Yet we want API users to get both/either, without making extra network requests.

We should consider either making a Fetch object that can be constructed and then when successfully invoked will hold the raw and translated data both, or a FetchResult object that is returned by a method and the result object holds the raw and translated data.