document how I made the first admin user for Zulip

docs/usage.rst

@@ -118,10 +118,23 @@ online document editing suite. Your can open documents in Onlyoffice by clicking
 them in Nextcloud. You can open new documents by clicking the "Plus" button in
 Nextcloud and selecting Document, Spreadsheet or Presentation.
 
-RocketChat
-~~~~~~~~~~
+Zulip
+~~~~~
+
+`Zulip <https://zulip./>`__ is a team chat application.
+
+Unfortunately, Zulip does not yet listen to the Stackspin roles, so once you
+have installed Zulip, you need to make one of your users the owner.  That allows
+that user to manage Zulip's settings from inside the application. This The owner
+can also edit other users' roles.
+
+For this, you have to replace ``<your email>`` in the the following command and
+run it on your cluster:
+
+```
+kubectl exec -n stackspin-apps zulip-0 -c zulip -- sudo -u zulip /home/zulip/deployments/current/manage.py change_user_role <your email> owner --realm 2
+```
 
-`RocketChat <https://rocket.chat/>`__ is a team chat application.
 
 Wekan
 ~~~~~