Add Graphite output

plugins/outputs/graphite/README.md

@@ -0,0 +1,13 @@
+# Graphite Output Plugin
+
+This plugin writes to [Graphite](http://graphite.readthedocs.org/en/latest/index.html) via raw TCP.
+
+Parameters:
+
+    Servers []string
+    Prefix  string
+    Timeout int
+
+* `servers`: List of strings, ["mygraphiteserver:2003"].
+* `prefix`: String use to prefix all sent metrics.
+* `timeout`: Connection timeout in second.