Add include to enable monitoring

Change-Id: I04c3405c8bd16504ba8c349dc3a2cda4352948fe
diff --git a/opencontrail/compute/cluster.yml b/opencontrail/compute/cluster.yml
index d10b361..5e92709 100644
--- a/opencontrail/compute/cluster.yml
+++ b/opencontrail/compute/cluster.yml
@@ -1,3 +1,5 @@
+classes:
+  - service.opencontrail.compute.cluster
 applications:
 - opencontrail
 parameters: