Added Citadel mail server
@@ -327,6 +327,7 @@
* [Mail-in-a-Box](https://mailinabox.email/) - Take back control of your email with this easy-to-deploy mail server in a box.
* [iRedMail](http://www.iredmail.org/) - Full-featured mail server solution based on Postfix and Dovecot.
+* [Citadel](http://www.citadel.org/) - Feature packed, easy, versatile, and powerful mail server, thanks to exclusive "rooms" based architecture.
## Monitoring
Crack Duck