(slowly) emulate functionality in `code` --> `core` + test

[jGaboardi]

(slowly) emulate functionality in code --> core + test

• code/
  • utils.py – #54
  • [x] city_fua
  • [x] fua_city
  • [x] read_sample_data
  • [x] read_parquet_roads
  • [x] graph_size
  • [x] load_usecases
  • viz/ – #61
    • context.py
      • [x] path
      • [x] location
      • [x] param_plot
      • [x] video
  • ....
  • etc...

xref #38, #54