[docs] [issue33666] Document removal of os.errno

STINNER Victor <vstinner@redhat.com> added the comment: Petr Viktorin started a thread on python-ideas as well: https://mail.python.org/pipermail/python-ideas/2018-May/051098.html ---------- _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue33666> _______________________________________