Verbose names for CITES Purpose codes and non-ISO location codes.

CITES has single-letter Purpose codes, e.g. B, G, M. Replaced them with verbose names to the drop-down filter, by adding a verboseNames property to the csv filter definition. This method can be extended to other filter categories that need verbose names.

CITES uses non-ISO location codes, e.g. XX for Unknown, which were causing error messages. Hard-coded interpretation of these codes in the makeCountryNameHash function.