Adds a SubLocation model

"The principle subdivision that a protected area geographically resides
within, given by an ISO 3166-2 sub-national code, e.g. autonomous
region, overseas territory, dependency, possession, etc. as long as it
does not already have an ISO 3166-1 alpha-3 character code in which case
it should be reported as a country. "
DataStandard handles SubLocation standardisation