Add stdenvNoCC

This is a standard environment that doesn't contain a C/C++
compiler. This is mostly to prevent trivial builders like runCommand
and substituteAll from pulling in gcc for simple configuration changes
on NixOS.

pkgs/build-support/substitute/substitute-all.nix

@@ -1,9 +1,9 @@
-{ stdenv }:
+{ stdenvNoCC }:
 
 args:
 
 # see the substituteAll in the nixpkgs documentation for usage and constaints
-stdenv.mkDerivation ({
+stdenvNoCC.mkDerivation ({
   name = if args ? name then args.name else baseNameOf (toString args.src);
   builder = ./substitute-all.sh;
   inherit (args) src;