Fix for including hgext in Windows compiled version.

From Shun-ichi GOTO via Mercurial mailing list.

setup.py

@@ -70,7 +70,8 b" setup(name='mercurial',"
                   for root, dirs, files in os.walk('templates')],
       cmdclass=cmdclass,
       scripts=['hg', 'hgmerge'],
-      options=dict(bdist_mpkg=dict(zipdist=True,
+      options=dict(py2exe=dict(packages=['hgext']),
+                   bdist_mpkg=dict(zipdist=True,
                                    license='COPYING',
                                    readme='contrib/macosx/Readme.html',
                                    welcome='contrib/macosx/Welcome.html')),