xmonad: improve post-process hook to support GHC 7.8.1
xmonad: improve post-process hook to support GHC 7.8.1

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