[Checkins] [zopefoundation/zope.configuration] edece6: Ensure consistent IRO for all objects.

[Jason Madden]

  Branch: refs/heads/issue49
  Home:   https://github.com/zopefoundation/zope.configuration
  Commit: edece6949e2cc0e39f5b6052e3b11ebb3484797f
      https://github.com/zopefoundation/zope.configuration/commit/edece6949e2cc0e39f5b6052e3b11ebb3484797f
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2020-03-22 (Sun, 22 Mar 2020)

  Changed paths:
    M .travis.yml
    M CHANGES.rst
    M setup.py
    M src/zope/configuration/_compat.py
    M src/zope/configuration/config.py
    M src/zope/configuration/fields.py
    M tox.ini

  Log Message:
  -----------
  Ensure consistent IRO for all objects.

This requires switching some tests to the plain unittest runner right now because of cyclic dependencies.

Fixes #49