remove outdated comments

Cython/Distutils/__init__.py

-# July 2002, Graham Fawcett
-#
-# this hack was inspired by the way Thomas Heller got py2exe
-# to appear as a distutil command
-#
-# we replace distutils.command.build_ext with our own version
-# and keep the old one under the module name _build_ext,
-# so that *our* build_ext can make use of it.
-
 from Cython.Distutils.build_ext import build_ext
-
-# from extension import Extension
+from Cython.Distutils.extension import Extension