Add openstack_node_role parameter

Add openstack_node_role parameter that will specify node role
primary|secondary. This metadata will be used by formulas as a
trigger to run one-shot operations.

Change-Id: I230590bc5f9d53960c6edaf7e37c44541d9c3342
Related-Prod: PROD-21267
diff --git a/sahara/server/cluster.yml b/sahara/server/cluster.yml
index cdb7b04..b01ab3d 100644
--- a/sahara/server/cluster.yml
+++ b/sahara/server/cluster.yml
@@ -9,6 +9,7 @@
       enabled: true
       version: ${_param:sahara_version}
       notification: false
+      role: ${_param:openstack_node_role}
       bind:
         address: ${_param:single_address}
         port: 8386