Refactoring of the GenderCodingNames type.

Broke method up into smaller methods.
Removed SupplementalFirstNames resources

Appended the SupplementalFirstNames resources into the GenderCodingNames
resource file and removed the SupplementalFirstNames file - this ensures
we have one 'encoding' file to manage.
Renamed GenderCodingName type.

Renamed the GenderCodingName type to a Person type.