- gcc/ld-wrappers have been factored out into a separate
    derivation.  This allows a working gcc to be installed in the user
    environment.  (Previously the Nix gcc didn't work because it
    needed a whole bunch of flags to point to glibc.)
    
  - Better modularity: packages can specify hooks into the setup
    scripts.  For instance, setup no longer knows about the
    PKG_CONFIG_PATH variable; pkgconfig can set it up instead.

  - gcc not longer depends on binutils.  This simplifies the bootstrap
    process.

svn path=/nixpkgs/trunk/; revision=816