Merge branch '15-disable-tls' into 'master'

Disable TLS if no certificate and key is provided (as by default exim4...

See merge request ix.ai/smtp!16

entrypoint.sh

@@ -50,6 +50,9 @@ if [ "$KEY_PATH" ] && [ "$CERTIFICATE_PATH" ]; then
 	chgrp Debian-exim /etc/exim4/exim.crt
 	chmod 640 /etc/exim4/exim.key
 	chmod 640 /etc/exim4/exim.crt
+else
+	  echo "MAIN_TLS_ENABLE = no" >> /etc/exim4/exim4.conf.localmacros
+	  echo "MAIN_TLS_ADVERTISE_HOSTS = !*" >> /etc/exim4/exim4.conf.localmacros
 fi
 
 opts=(