Add input/output classes for Telegraf

Change-Id: I3e7caa4835af9082daf27ca4d882b682fa72fd28
diff --git a/telegraf/agent/output/prometheus.yml b/telegraf/agent/output/prometheus.yml
new file mode 100644
index 0000000..952bc13
--- /dev/null
+++ b/telegraf/agent/output/prometheus.yml
@@ -0,0 +1,11 @@
+parameters:
+  _param:
+    telegraf_agent_prometheus_port: 9126
+  telegraf:
+    agent:
+      output:
+        prometheus_client:
+          bind:
+            address: 0.0.0.0
+            port: ${_param: telegraf_agent_prometheus_port}
+          engine: prometheus