refactor: move all requires-* to common folder

[Borda]

This is just a suggestion, and fell free to reject it fro any reason, but I believe this would make the project navigation easier as all requirements files will we grouped in a single folder and not pealing in the root 🦩

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[T4rk1n]

Sorry it took a long time to review, I couldn't decide if I like this change or not.

On one hand I like to have them easily accessible at the root for ease of use and that way our dependencies are right on the github front page for everyone to see.

But putting them in a subfolder is actually a bit better for completion on the shell and the root is kinda crowded making the requirements files requires scrolling to get to them.

I would just rename the requires folder to requirements to be more like the standard requirements.txt of Python projects then I think we are good with this change.

cc @ndrezn @gvwilson

[gvwilson]

thanks @T4rk1n - @Borda, are you OK making the suggested change and pushing again?