Add support for Grafana

This patch adds support for Grafana and provide a new dashboard.
diff --git a/metadata/service/support.yml b/metadata/service/support.yml
index 5376c55..2d10c66 100644
--- a/metadata/service/support.yml
+++ b/metadata/service/support.yml
@@ -9,3 +9,5 @@
         enabled: true
       sphinx:
         enabled: true
+      grafana:
+        enabled: true