Kqueen service support for Drivetrain

initial commit
-glusterfs volumes
-docker stack
-haproxy

related-us: https://mirantis.jira.com/browse/PROD-18445
Change-Id: Icf9838c1d451cf281251434bbc63e60aa7b206cb
diff --git a/docker/swarm/stack/kqueen_mail.yml b/docker/swarm/stack/kqueen_mail.yml
new file mode 100644
index 0000000..dd03688
--- /dev/null
+++ b/docker/swarm/stack/kqueen_mail.yml
@@ -0,0 +1,16 @@
+parameters:
+  _param:
+    mail_server_hostname: mail
+  docker:
+    client:
+      stack:
+        kqueen:
+          service:
+            mail:
+              image: modularitycontainers/postfix
+              environment:
+                MYHOSTNAME: ${_param:mail_server_hostname}
+          network:
+            default:
+              external:
+                name: kqueen_backend