feat: add debug option to CLI

[jedluhmann]

Added a new debug feature. See the following commits for details:

• cf5809f
• ec40b44

[jedluhmann]

@andreyvit I don't understand why you closed PR #135 basically saying that patch was too big. That PR only changes one file, adding just one test.

All of my PRs build on top of the previous one, so the latter ones appear to have a lot of unrelated changes, but that is not really the case. I've put a lot of effort into explaining my work to make it easier for you to review the changes and I've spent a lot of time updating the test cases, so you can have confidence in my work.

As far as styling my code like the rest of the project, I'm using ESLint to ensure that my code is formatted according to the industry wide standard. Is it just a matter of removing semicolons? I'm happy to do that if that's what you want.