swi-prolog: updated version + packs support
swi-prolog: updated version + packs support

Using "extraPacks" and "extraLibraries" arguments
it is possible to create fully functional virtual-envs
for SWI-Prolog projects.
(In a way similar to what "ghcWithPackages" does for Haskell)

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