lib/customization: Improve callPackage error message for missing args
lib/customization: Improve callPackage error message for missing args

This uses the levenshtein distance to look through all possible
arguments to find ones that are close to what was requested:

  error: Function in /home/infinisil/src/nixpkgs/pkgs/tools/text/ripgrep/default.nix
    called without required argument "fetchFromGithub",
    did you mean "fetchFromGitHub" or "fetchFromGitLab"?

With https://github.com/NixOS/nix/pull/3468 (in current nixUnstable) the error
message becomes even better, adding line location info

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs