Describe: display CSI Volume source attributes

[adietish]

related to #553

#553 currently doesn't print the volume attributes for a CSI Volume Source. kubectl does the following:

https://github.com/kubernetes/kubectl/blob/b315eb8455a7d5c11ed788d1592b4afeca85771d/pkg/describe/describe.go#L1431

printCSIPersistentVolumeAttributesMultiline(w, "VolumeAttributes", csi.VolumeAttributes)

func printCSIPersistentVolumeAttributesMultilineIndent(w PrefixWriter, initialIndent, title, innerIndent string, attributes map[string]string, skip sets.String) {
	w.Write(LEVEL_2, "%s%s:%s", initialIndent, title, innerIndent)

	if len(attributes) == 0 {
		w.WriteLine("<none>")
		return
	}

	// to print labels in the sorted order
	keys := make([]string, 0, len(attributes))
	for key := range attributes {
		if skip.Has(key) {
			continue
		}
		keys = append(keys, key)
	}
	if len(attributes) == 0 {
		w.WriteLine("<none>")
		return
	}
	sort.Strings(keys)

	for i, key := range keys {
		if i != 0 {
			w.Write(LEVEL_2, initialIndent)
			w.Write(LEVEL_2, innerIndent)
		}
		line := fmt.Sprintf("%s=%s", key, attributes[key])
		if len(line) > maxAnnotationLen {
			w.Write(LEVEL_2, "%s...\n", line[:maxAnnotationLen])
		} else {
			w.Write(LEVEL_2, "%s\n", line)
		}
	}
}