I will use the same format as the ISO 3166-1 JSON to make parsing
easier. I will add a new "cgspace_name" key to indicate our custom
name, though the codes will map to the standard ISO 3166-1 codes.
If an item has country metadata (cg.coverage.country) and no alpha
codes we check for name matches in ISO 3166 and add alpha_2 codes.
The name matching checks for a case-insensitive match on either an
ISO 3166-1 name, official name, or common name.
Our Java class needs to match the input JSON structure exactly, but
we can't use "3166-1" as a variable name so we tell GSON to use the
name "3166-1" when deserializing to countries.