Kublet volume stats on PowerFlex

Hi @koj6 ,

We provide capacity and performance metrics via the project : https://github.com/dell/karavi-observability

You can see the collected names from : https://github.com/dell/karavi-metrics-powerflex 

The names are different (i.e. not prefixed with kubelet_ but powerflex_).

Note that we don't have the used capacity metrics.

Let us know if you are able to deploy the observability module.