Incorrect behaviour for hideOverlayOnDragAndResize option

After first drag/resize attempt, overlay is shown _only_ when dragging/resizing (i.e. the opposite of what the flag should do).

Attached change hides when starting dragging and shows again when stopping dragging. Needed to remove `display:block` in `makeOverlayPositions` - if that was needed it may need to be converted to a conditional block/none or similar.