Add Glottolog field to all lang and keyboard repo docs

[snomos]

It should be a replacement variable like __UND__ etc. The idea is that the Glottolog ID is added when a new language or keyboard repo is created. For existing repos it has to be added manually.

When this is added, we'll use it to enhance our generated documentation.

To do:

• add Glottolog ID to lang repos
• add Glottolog ID to keyboard repos

[snomos]

Det skulle kunne vera ei eiga lita fil, t.d. .glottologid.txt i rota av kvart repo.

[flammie]

har lagt til koder fra https://glottolog.org/resourcemap.json?rsc=language, det er en del macrokoder og sånt som mangler i glottolog og ble tom filer,