RFE: Add Territory Containment (Continents and subregions) #474

As I can see in the last CLDR there is a supplementary data about the Continent names and country containment:

http://www.unicode.org/cldr/charts/latest/supplemental/territory_containment_un_m_49.html

The idea is to get information about the region where a country is, as example here is one example of the data:

World [001] - Americas [019] - South America [005] - Argentina [AR]

(Yeah World is the super region, so we are outer world colonization proof, better safe than sorry!)
All the data is a kind of tree that open in a more detailed region until you reach the Country and Timezone (not sure why that, but is there).

I can try to work it in a PR to add this if there is concent to do it.
I also like to discuss a little bit with some of the core devs or someone with experience in contribute code to this proyect what is the better way to implement this and keep the interfaces of the API consistent with the rest of the information provided.