[Checkins] [zopefoundation/Zope] b28fe4: Update to current releases of the dependencies.

[Michael Howitz]

  Branch: refs/heads/update-deps
  Home:   https://github.com/zopefoundation/Zope
  Commit: b28fe41fdd12f73a1d0800491340f3524dd9d551
      https://github.com/zopefoundation/Zope/commit/b28fe41fdd12f73a1d0800491340f3524dd9d551
  Author: Michael Howitz <mh at gocept.com>
  Date:   2019-06-19 (Wed, 19 Jun 2019)

  Changed paths:
    M CHANGES.rst
    M versions-prod.cfg
    M versions.cfg

  Log Message:
  -----------
  Update to current releases of the dependencies.