Debug custom selection, and clear selected nodes when mode is changed

Author: mbastian

modules/engine-core/src/main/java/org/gephi/viz/engine/status/GraphSelectionImpl.java

@@ -94,6 +94,7 @@ public void addSelectedNode(Node node, Collection<Node> neighbours) {
     @Override
     public void clearSelectedNodes() {
         this.nodes.clear();
+        this.nodesWithNeighbours.clear();
     }
 
     @Override
@@ -177,6 +178,7 @@ public GraphSelectionMode getMode() {
     public void setMode(GraphSelectionMode mode) {
         if (mode != null) {
             selectionMode = mode;
+            clearSelection();
         }
     }