don't remove volume shadow copies by default
don't remove volume shadow copies by default

Per 
http://answers.microsoft.com/en-us/windows/forum/windows_vista-performance/understanding-and-getting-rid-of-device-listing-of/9a39e843-2749-4f27-a64a-09f50eecf736
it might be undesirable to remove these in case of later resizing of
restore space, etc.
kevinoid/remove-nonpresent-devices