adding no-data screenshots to readme (#50)

Author: perryqh

README.md

@@ -103,4 +103,5 @@ Right now this tool sends metrics to DataDog only. However, if you want to use t
 
 We recommend the use of the dashboard that is shipped with this gem. You can create a new dashboard and then click "import dashboard JSON" to get a jump start on tracking your metrics. Note you may want to make some tweaks to these dashboards to better fit your organization's circumstances and goals.
 
-[Dashboard JSON](docs/dashboard.json)
+- [Dashboard JSON](docs/dashboard.json)
+- [Screenshots](docs/screenshots.md)

docs/screen-1.png

@@ -0,0 +1,6 @@
+# Screenshots 
+Below are the datadog screenshots produces from the sample [dashboard.json](./dashboard.json)
+
+
+![alt screenshot](./screen-1.png)
+![alt screenshot](./screen-2.png)