Integrate RDC with Grafana

A new Grafana dashboard file rdc_grafana_dashboard_example.json
has been added to the folder python_binding. User can import
this dashboard to monitor multiple compute nodes.

To display the host name only in the dashboard, the
rdc_prometheus_example.yml is also changed to create a new label
short_instance which will not have the port number.

Change-Id: I9ab91838006d59c8dcb5fea01decb8c799484e1d

python_binding/rdc_prometheus_example.yml

@@ -12,6 +12,12 @@ scrape_configs:
     # metrics_path defaults to '/metrics'
     # scheme defaults to 'http'.
 
+    # Remove the port for display
+    relabel_configs:
+    - source_labels: [__address__]
+      regex: '([^:]+):\d+'
+      target_label: short_instance
+
     file_sd_configs:
     - files:
         - 'prometheus_targets.json'