[XML-SIG] Fixing PyXML

[Martin v. Loewis]

>   The checkins I just made (adding _xmlplus.parsers.expat and
> _xmlplus.sax.xmlreader) help; test.test_pyexpat passes.  test.test_sax
> still fails with "cannot import name InputSource".  Adding handler.p
> doesn't fix this (though it needs to be added as well).

Just adding xmlreader and handler is not enough; the new classes must
be deleted from saxlib/saxutils/sax[2]exts. I'll look into it.

Regards,
Martin