Error loading viridis from `example_d.py`

[mfisher87]

See: #58 (comment)

$ python -m viscm --uniform-space buggy-CAM02-UCS -m Bezier edit /tmp/option_d.py
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "/home/robatt/Projects/_external/viscm/viscm/__main__.py", line 8, in <module>
    cli()
  File "/home/robatt/Projects/_external/viscm/viscm/cli.py", line 114, in cli
    mainwindow = gui.EditorWindow(figureCanvas, v)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/robatt/Projects/_external/viscm/viscm/gui.py", line 1157, in __init__
    self.max_slider.setValue(viscm_editor.max_Jp)
TypeError: setValue(self, a0: int): argument 1 has unexpected type 'float'