Add JavaFX ModelElementView with DragAndDrop functionality for graphical and tree-table editors.
Creation of a new JavaFX-based ModelEditorView (right to the editor) in
order to replace the old SWT-based implementation. The view shall be
similar to the old one, hence control code may be reused.
Needs new implementation of drag and drop mechanism from ModelEditorView to DiagramEditor.
(from redmine: issue id 3921, created on 2020-01-27, closed on 2020-03-04)
- parent #3906