[Checkins] [zopefoundation/ZopeUndo] 052332: Add support for Python 3.7.

[Jürgen Gmach]

  Branch: refs/heads/update-versions
  Home:   https://github.com/zopefoundation/ZopeUndo
  Commit: 0523329185d565126c28253bd265468d4182775e
      https://github.com/zopefoundation/ZopeUndo/commit/0523329185d565126c28253bd265468d4182775e
  Author: Jürgen Gmach <juergen.gmach at apis.de>
  Date:   2019-04-09 (Tue, 09 Apr 2019)

  Changed paths:
    M .travis.yml
    M CHANGES.rst
    M setup.py
    M tox.ini

  Log Message:
  -----------
  Add support for Python 3.7.

This closes #3.

modified:   .travis.yml
modified:   CHANGES.rst
modified:   setup.py
modified:   tox.ini