Activation emails were using django's sites framework which always has
the domain set to zulip.com.
(imported from commit b81eae96e1a75b64dd93970760b869f3271ce88c)
A stream is vacant when it has no subscribers and occupied when it has at least
one subscriber.
We have a slightly odd model where stream creation is conflated with
subscription creation. Streams are created by attempting to subscribe to a
stream that doesn't exist. We also hide streams with no subscribers from users
to make it seem like they've gone away. However, we can't actually remove those
streams because we want to preserve history.
This commit moves us towards a separation of these two concepts. By sending
events for stream creation, occupation, vacancy, and deletion, we allow clients
to directly observe the global state of streams rather than indirectly observing
subscription information. A more complete solution would involve adding a view
for explicitly creating streams without subscribing to them.
This commit does not handle the intricacies of invite-only streams. We
currently simply do not send these events for invite-only streams.
(imported from commit 5430e5a5eecefafcdba4f5d4f9aa665556fcc559)
Jason Michalski
Zev Benjamin
Jessica McKellar
Steve Howell