Removing groups that don't exist

[danielepolencic]

When a meetup doesn't have an organizer for longer than 1 month, meetup.com will delete it.

What happens when a group is deleted:

• The page of the group does not exist anymore.
• The RSS feed replies with: 403 {UNKNOWN=[BAD ARGS] null memberOfIfPrivate}.

Example:

• https://www.meetup.com/PHL-Cloud-Native-Meetup-Group/events/rss/
• https://www.meetup.com/PHL-Cloud-Native-Meetup-Group

There should be a way to detect this and purge old (unmaintained) groups.