BUG: Fix memory override for vtkContourFiler in isofillpipeline.
This resulted in vtkStripper to generate double coverage of isocountours which resulted in messed-up patterns. Also adjusted plot patterns to easier to discriminate.:MERGED:
This resulted in vtkStripper to generate double coverage of isocountours which resulted in messed-up patterns. Also adjusted plot patterns to easier to discriminate.:MERGED: