[Tracker] Implement Territory modules

[behnam]

This model is going to be directly based on ISO 3166-1, ISO 3166-2 and M-49 data sets, with addition of private-use cases from CLDR (like QO and its relationship) for compatibility.

Model

The single Territory model will represent all levels of world/country regions, including:

• Country Groupings
  • The World
  • Continents
  • Subcontinents
  • Other Groupings (like EU and Latin America)
• Countries (ISO 3166-1)
  • Independent / sovereign states
  • Dependent Territories
• Country Subdivisions (ISO 3166-2)
  • Tree-like hierarchy
  • Zero, one or more levels

This will be similar to the region part of BCP-47 codes, plus the Subdivision (sd) Unicode extension to it.

Data

We need proper data sources to build this. The data sources should be kept up-to-date in sync with their source Registration/Maintenance Authorities (and not based on a software release schedule), and the compiled data should be kept up-to-date as well with clear logic and automated updates.