VTK - general AJAX bugfix: don't add check/uncheck all if no resources listed in content
VTK - general AJAX bugfix: don't add check/uncheck all if no resources listed in content

vtkio/vtk,vtkio/vtk,vtkio/vtk,vtkio/vtk,vtkio/vtk,vtkio/vtk,vtkio/vtk,vtkio/vtk