message: Update README.md
  Add PCM Grafana screenshot
diff: @@ -13,3 +13,5 @@ Installation of the grafana front-end (can be on any *host* system with connecti
  3. (Download once and) start docker containers on the *host*: `sh start.sh http://target_system_address:80`
  4. Start your browser at http://*host*:3000/ and then login with admin user, password admin . Change the password and then click on "**Home**" (left top corner) -> "Processor Counter Monitor (PCM) Dashboard"
  5. You can also stop and delete the containers when needed: `sh stop.sh`
  +
  +![pcm grafana output](https://raw.githubusercontent.com/wiki/opcm/pcm/pcm-dashboard.png)
  