hackage2nix.hs: add override to keep older versions of primitive
hackage2nix.hs: add override to keep older versions of primitive

psibi/cabal2nix,jb55/cabal2nix,spencerjanssen/cabal2nix,Fuuzetsu/cabal2nix,bennofs/cabal2nix,dmalikov/cabal2nix,gridaphobe/cabal2nix