Shorten the main README.md — keep only core features and usage, move the rest to separate docs

[esmaeelE]

The main README.md has grown quite long and now contains a lot of information beyond the essentials.
I suggest splitting its content into multiple separate Markdown files.

[BigBodyCobain]

I would LOVE to do that, but I've realized people always mention how I didn't mention this or that in the readme, and how it is an important feature that should be stated and elaborated on. I've found that I'd rather be verbose than concise in this regard. I appreciate your suggestion, though.

[esmaeelE]

OK, I understand.
But if you are agree I can provide (as pull request) a collapsible version of README.md with details and summary tags.

Something like this attached image.

[BigBodyCobain]

That would actually be phenomenal!

[esmaeelE]

That would actually be phenomenal!

Here you are

#393