Hide Datastores In List With No Active Versions

in a datastore-list operation, for non-admin, filters out
datastores that either have no versions or have no active
versions for non-admin users. admins continue to see all
datastores, active or inactive, in a datastore-list
operation.

Change-Id: Iccaf9ae59469fd0f4cb346ee258d3132eed83660
Co-Authored-By: Andrey Shestakov <ashestakov@mirantis.com>
Closes-Bug: #1290617
Merge "Hide Datastores In List With No Active Versions"