Load scene into Slicer with empty vtk errors

Dear developers,


When I try to load a scene in Slicer, error happened,

VTK may report it as an error when I attempt to read or write an empty file, while it may be normal that a fiber is empty.
According to Iassoan, a possible fix would be to apply the same technique as it is done in the model storage node: use the SkippedNoData write state to indicate that the file is expected to be empty.
Best wishes,
Zhang Kening