* Streamline the stdenv bootstrap and resulting closure by removing

  some redundant builds (e.g., GMP was built three times).
* Updated GMP to 5.0.2.
* Updated PPL to 0.11.2.
* Remove ad hoc flags to build GCC's dependencies statically.
  Instead, use the ‘makeStaticLibraries’ stdenv adapter.
* Build GMP with C++ support by default.

svn path=/nixpkgs/branches/stdenv-updates/; revision=30891