Feat/use webgl interactive plot

* feat/nml2matplotlib: (23 commits)
  feat(morph-plot-3d): implement min width
  feat(morph-plot-2d): implement option to provide minimum line width
  docs: add PlotMorphology to docs
  feat: add plotly etc to dev requirements
  chore: add note about WebGL to 3D morph plotter
  feat(morphology-plot): add 3D interactive plotter
  feat: add pynml-plotmorph script and update man pages
  test(morphology-plotter): complete tests
  feat(morphology-plotter): add scalebar
  test(morphology-plot): test with simple and complex morphology
  feat(morphology-plot): check for all variations of plane names
  feat(plot): add tests for morphology plotter
  test(plot): copy over init file
  tests: init tests for plotting
  chore: remove unused import
  feat: make utils a package by adding __init__.py
  feat(morph-plotting): refactor and add dummy 3d plotter function
  chore: add utils submodule to packages
  refactor(utils): move argparser to utils module
  chore: format
  ...