Fix vtk fiber bundle writer

   COMP: change VTK build script to work with all CMake Generators
    
    BUG:  --simpleTensorModel flag went away
    
    Replaced with --fullTensorModel, which defaults to false.
    
    COMP: try to figure out VTK Output Data problems in Slicer
    
    See https://www.icts.uiowa.edu/jira/browse/PREDICTIMG-3505 The
    complaint is that Slicer is not liking the VTK files made
    by fiberbundle.