users with APIs with broken source URLs should be notified or APIs should be removed or transferred

[marcodarko]

An aggregation of the current data shows a number of APIs with broken URLs: https://smart-api.info/api/query/?q=__all__&fields=_status.refresh_status,info.title&size=1000&raw=1&aggs=_status.refresh_status

A discussion about what steps to take with these items is perhaps needed to improve the quality of our registry.