[Dovecot] Use events to kill supervisord when main proc dies

[Postfix] Use events to kill supervisord when main proc dies
[SOGo] Use events to kill supervisord when main proc dies

data/Dockerfiles/dovecot/supervisord.conf

@@ -1,6 +1,7 @@
 [supervisord]
 nodaemon=true
 user=root
+pidfile=/var/run/supervisord.pid
 
 [program:syslog-ng]
 command=/usr/sbin/syslog-ng --foreground --no-caps
@@ -17,3 +18,7 @@ autorestart=true
 [program:cron]
 command=/usr/sbin/cron -f
 autorestart=true
+
+[eventlistener:processes]
+command=/usr/local/sbin/stop-supervisor.sh
+events=PROCESS_STATE_STOPPED, PROCESS_STATE_EXITED, PROCESS_STATE_FATAL