Move the list of countries to an external file… maybe?

[taflanidi]

Prerequisites

• Put an X between the brackets on this line if you have done all of the following:
  • read our Wiki;
  • read the entire Known issues section;
  • checked that my feature request isn't already filled;
  • searched StackOverflow's input-mask tag for similar problems.

Summary

Let there be a *.CSV-or-something file with the list of all countries to pick up from.

https://github.com/google/libphonenumber/tree/master/resources

Motivation

It would be easier to expand & maintain. Maybe.

Describe the solution you'd like

Make sure to make it localisable :D

https://developer.apple.com/documentation/xcode/bundling-resources-with-a-swift-package
https://developer.apple.com/documentation/xcode/localizing-package-resources

Describe alternatives you've considered

Leave the sources as is.