Add country languages

[leandro-lugaresi]

HI!
Thanks for the project, this is awesome work!

I'm using your library to import geolocation data and need the official languages by a country.

To solve that, I'm building a list of country codes and languages.

WDYT about put this info inside the library? If ok for you I can open a PR for these.

[biter777]

Yeah, PR would be great!

Of course, I considered this functionality, but my hands never got to it. :)
Imho, the language codes should, if possible, be compatible with language.Tag
(see https://godoc.org/golang.org/x/text/language#Tag and https://github.com/golang/text/blob/master/internal/language/compact/tables.go).

[lucasdss]

Is anyone working on this?

[futuarmo]

@leandro-lugaresi, please, publish your table of languages somewhere

[biter777]

Is anyone working on this?

Not yet

[loeffel-io]

we need this too!

[curiosport]

A reference I guess:
https://saimana.com/list-of-country-locale-code/