Add link to explanation when introducing a new operator
Add link to explanation when introducing a new operator

The logical implication operator is included in this section but never explained. It might stump new readers with a pretty uncommon operator, and it's never referenced explicitly.
rycee/nix,rycee/nix,rycee/nix,NixOS/nix,rycee/nix,NixOS/nix,NixOS/nix,rycee/nix,NixOS/nix,NixOS/nix