Map organizations to the accounts

[This list of accounts](https://github.com/github/government.github.com/blob/gh-pages/_data/governments.yml) is really impressive, but since they aren't mapped to which organization they belong to, it's hard to reuse the data in any kind of automated way (like batch importing it to Wikidata). Can it be added as a key for each account?

Start with _data/governments.yml, which contains the accounts described in the issue, and inspect how each account is structured. Add an organization key for every account so the list can be reused for automated importing, including the intended organization mapping in each entry.

Scritto dal modello di indicizzazione a partire dal testo della issue.