Type::Tiny::Enum should have better docs around sorter

[SineSwiper]

So, Type::Tiny::Enum doesn't honor sorter overrides. I was going to originally post that as the bug here, but I realized that the values can just be sorted in order and that would fix the problem.

However, there isn't really anything in the docs that mention how Enum has its own sorter or that it doesn't allow you to use sorter. I believe there should be some additional docs about it in Attributes and Methods, and perhaps it should also croak in the same way the other "illegal" attributes do.

EDIT: Type::Tiny::Enum->sorter is also non-deterministic for outside values. So, perhaps a custom sorter isn't completely useless after all?