Include sources in CSV
The sources are important when importing the candidates into another database, so we might wanna include them in the CSV output.
I'm not sure quite how we would do this; obviously multiple sources (one per edit) are linked to a person and they often won't make sense without the associated change derived from the versions array.
My feeling is that for importing the candidates into another database you'd want to use the API, as candidates_import_from_live_site does.
Well, I was thinking it can be treated as a bibliography - that's probably better than nothing, right? The two major issues I see are: the sources field being used for things other than sources, as is often the case; and identifying changes that negate a previous change.