Round trip experiment

[ibbem]

I'm quite happy about this solution because it seems quite flexible (even though maybe a bit overkill).
Nonetheless, feel free to enhance the formatting, output, the example, etc.
Maybe it's a good idea to use a smaller example (or add a second example) because the terms get big really fast.
The last commit is optional. Just something I thought about while being sleepy :)

[pmbittner]

Hi @ibbem ,
thank you very much, the experiment looks really great! ❤️ I removed the last commit (starting trip at OC) and pushed it to a new branch for now. I like the idea but for the submission, we should be consistent with the paper.

The placing of commata is a bit inconsistent. Sometimes there are commas, sometimes not. Also maybe we do not have to put them on a newline. I tried to adapt it myself but I am unused to a writer monad. I will check later.

Thank you!