kickoff: Replace Kicker DragHelper with Qt Quick Drag
Originally, I thought it wasn't possible to use Qt Quick Drag here, but then I found out I could use Item::grabToImage()'s function callback parameter to set Drag.imageSource.
Originally, I thought it wasn't possible to use Qt Quick Drag here, but then I found out I could use Item::grabToImage()'s function callback parameter to set Drag.imageSource.