Idiomatic Rust and misc. updates

[Riceman2000]

There are a few things that I would like to change about the source code of this project to make it follow some of Rust's idioms.

• Split the functional code into a Library Crate so it could be used by others
  • After this change consider uploading to crates.io
• Error handling appropriate for a library using std::log -> https://docs.rs/log/latest/log/
  • Also critical errors should not panic, instead they should pass that error back
  • An error type for the library could be made to make this easier with thiserror https://docs.rs/thiserror/latest/thiserror/
• Some unit testing
  • Incorporate testing into pipeline

Saw the YouTube video and I'd love to contribute, I'll submit a PR with a few changes.

Thanks!