Merge remote-tracking branch 'origin/master' into stdenv-updates.

Conflicts:
	pkgs/development/interpreters/perl/5.16/default.nix
	pkgs/tools/networking/curl/default.nix
	pkgs/top-level/all-packages.nix
	pkgs/top-level/release-python.nix
	pkgs/top-level/release-small.nix
	pkgs/top-level/release.nix