euler-paths (v0.1.0)

• Code based on the blog post: https://mjhdata.netlify.app/blog/euler-paths/
• A tiny library of functions in src/euler.mac.
• A test script src/eulersberg.mac to match the blog post example.
• Using a custom graph type, instead of the Maxima graphs library.
• Commands to install dependencies (make install) and run test script (make run).
• Simple parsing of the test script output to remove Maxima verbose output.
• Tested on Ubuntu 20.04.6 LTS (Focal Fossa) with Maxima 5.43.2.