Show plus sign during drag-and-drop copying in Catalog

[davmay]

In the List and Tree panes, XYplorer behaves in the usual Windows manner by displaying a small + at the cursor during a drag-and-drop copy as opposed to a move. Although drag-and-drop copying works perfectly well within the Catalog -- that is, when we are copying a Catalog item to another position in the Catalog -- the + does not appear, so there is no visual feedback to reassure us that we are doing a copy. It would be helpful to make this behavior uniform in all panes.

[admin]

True. Done.