Submitted by Nicolas Rannou <nicolas_rannou@hms.harvard.edu>

vtkGraphLayoutView
-> new method: void SetEdgeSelection(bool) - modify the representation
   variable EdgeSelection.
-> new method: bool GetEdgeSelection() - get the representation variable
   EdgeSelection.

vtkRenderedGraphRepresentation
-> new variable: bool EdgeSelection - default true=edges will be
selected
-> new method: void SetEdgeSelection(bool) - modify EdgeSelection value.
-> new method: bool GetEdgeSelection() - get EdgeSelection value.

Change-Id: I7f438386fd119fa9a819dffeea864f64de29ebaa