Add Angular Momentum builtins...

[rocky]

which starts a Quantum Mechanics section.

TODO:

• Unit tests for errors.
• Ensure function attributes are correct
• Ensure we error on what we are supposed to and not on what we do not

[mmatera]

Something that I am not sure about this is whether these functions belong to a quantum mechanics section, or to other modules (PauliMatrix to linear algebra, ClebschGordan, ThreeJSymbol and SixJSymbol to "Combinatorial Functions" (https://reference.wolfram.com/language/guide/CombinatorialFunctions.html) , etc. Otherwise, we should put the special polynomials also under this category.

[rocky]

Something that I am not sure about this is whether these functions belong to a quantum mechanics section, or to other modules (PauliMatrix to linear algebra, ClebschGordan, ThreeJSymbol and SixJSymbol to "Combinatorial Functions" (https://reference.wolfram.com/language/guide/CombinatorialFunctions.html) , etc. Otherwise, we should put the special polynomials also under this category.

I am following https://reference.wolfram.com/language/guide/FunctionsUsedInQuantumMechanics.html

We will also have to deal with the duplication somehow. But that is yet another battle with autodoc for some other time.

Otherwise, we should put the special polynomials also under this category.

Again I am following the organization cited above and we'll have to figure out how to deal with duplication under sections.

[rocky]

This weekday's activity will probably be finish the development guide for Curl, and I might also add KroneckerProduct since I now see what is up with sympy Matrices.