[librender] add forgotten connection operations when opening graph editor

src/libRender/RadiumNBR/Gui/NodeGraphControllerGui.cpp

@@ -140,6 +140,7 @@ buildNodeGraphControllerGui( NodeBasedRenderer* renderer,
                         {
                             std::cerr << "Loading nodegraph " << renderer->getJsonFilePath()
                                       << " in the editor." << std::endl;
+                            nodeEditor->disconnectAll();
                             nodeEditor->scene->clearScene();
                             renderer->getRenderGraph()->clearNodes();
                             QByteArray wholeFile = file.readAll();
@@ -150,6 +151,7 @@ buildNodeGraphControllerGui( NodeBasedRenderer* renderer,
                                                                      " - " +
                                                                      renderer->getJsonFilePath() )
                                                             .c_str() );
+                            nodeEditor->connectAll();
                         }
                     }
                 }