[RFE] Ability to back VM clones/snapshots by HW snapshots

Issue

This request is about the ability to use the snapshot capability commonly present in enterprise grade SAN storage devices to create clones and snapshots of both off- and on-line VM:s.
This feature would allow to create clones and snapshots of VM:s, even with large disks, much faster then what would be possible without using the storage's snapshot functionality.