Add line image upload option to convert a line image into a path

[markroland]

• http://sunnybala.com/2018/09/10/python-etch-a-sketch.html
• https://create.arduino.cc/projecthub/iot_lover/arduino-drawing-via-web-using-step-motor-controller-cb5f33
• https://mathematica.stackexchange.com/questions/133280/draw-image-as-a-continuous-line-drawing
  • https://networkx.github.io/documentation/stable/tutorial.html

[markroland]

See also "Traveling Salesman Problem", or "TSP Art".

Stipple generator, Voronoi Diagram https://www.evilmadscientist.com/2012/stipplegen2/