For everyone to track what's going on worldwide. :)
Notes from merged tasks:
- Think about where this calendar should live. Outreach / Phabricator / elsewhere?
- Clearly differentiate if they are Wikimedia-related events or events outside of the movement. Consider the audience.
Closing this old task as per https://phabricator.wikimedia.org/T115178#5704787
Nowadays this might be https://discuss-space.wmflabs.org/c/events/l/calendar .
Rxternal options like "Google Calendar" would violate the privacy of all users.