Revert "enable preConfigure for python packages again"

This reverts commit a513314290ba0d78400ea4902301f421e0fecdd2.

svn path=/nixpkgs/branches/stdenv-updates/; revision=32642

pkgs/development/python-modules/generic/default.nix

@@ -17,8 +17,6 @@
   # pollute the user environment.
   pythonPath ? []
 
-, preConfigure ? "true"
-
   # distutils registers dependencies in .pth (good) but also creates
   # console_scripts for dependencies in bin/ (bad). easy_install
   # creates no scripts for dependencies (good) but does not register
@@ -86,7 +84,7 @@ python.stdenv.mkDerivation (attrs // {
 
     # enable pth files for dependencies
     export PYTHONPATH="${site}/lib/${python.libPrefix}/site-packages:$PYTHONPATH"
-  '' + preConfigure;
+  '';
 
   # XXX: I think setuptools is not needed here
   pythonPath = [ setuptools site ] ++ pythonPath;