Add docker-mailserver (default config to track changes)
diff --git a/TODO.on.site b/TODO.on.site
index c0b18ac..3409510 100644
--- a/TODO.on.site
+++ b/TODO.on.site
@@ -10,6 +10,11 @@
 Get containers up:
 * `docker-compose up`
 
+Mail setup:
+* A 'gerrit@' mail account will be added automatically
+* See `docker-compose exec mailserver setup` for more
+* Add account or alias for 'postmaster@'
+
 When the containers are up run `certbot`:
 * Once `docker-compose -f sa-certbot.yml run new`
 * Every x < 30 days `docker-compose -f sa-certbot.yml run renew`