Use GeoNames for country field

[Andrew67]

Use GeoNames' country info API combined with a CRON job to enrich database country data, no matter the source.
Their license allows storage of such data, and the API simply returns the country code.

API: https://www.geonames.org/export/web-services.html#countryInfo
Example URL: http://api.geonames.org/countryCode?lat=35&lng=139&username=demo
Result is just the string, so a simple file_get_contents could be employed: https://www.php.net/manual/en/function.file-get-contents

Considerations:

1. A "last update" field or capturing the lat/lng at the time of update, to handle stale entries after the data is populated.
2. Attribution section for country data in sources.json, separate from the usual data source information.