Add docs/wiki

[AgentRBY]

Add documentation or a wiki page on GitHub so the community can do documentation!

I could try to describe the basic stuff.

[zardoy]

I was thinking of creating a website within repository for a long time. But probably wiki is fine for the first time (we can then move contents to the website at any time). I've created a wiki page, so you can try to add any content you like. Feel free to experiment, I'll look into it!

Another thing that I don't really like about wikis is that they are too unrestrictive (everyone can edit them without a notice).

[AgentRBY]

In theory, you can create a documentation site using Vitepress or other similar tools, and deploy to Github Pages.

But thanks for the wiki