equal?
eqv?
eq?
Use the same examples for each so it's easier to compare how the behavior differs.
Part of the clarification is duplicating information about numbers and character in the documentation of `eqv?`. Since those two type are the only special cases of `eqv?`, the duplication seems helpful and managable.
The layer is now redundant, since everything left in "pkgs" is in the "racket-pkgs" category.