Add examples for each frequently used GAs

[utensil]

I need a symbolic cheatsheet similar to https://observablehq.com/@enkimute/ganja-js-cheat-sheets for at least the GAs in https://github.com/enkimute/ganja.js#the-algebra-function . Particularly, I'm surprised that we don't have a simple A*B full expansion for any GA in our examples.

[eric-wieser]

In the form of a notebook, perhaps?

[utensil]

Yes, definitely. I'll do this along with the proofs for them, mostly first examples here, then proofs there.