[Checkins] [zopefoundation/z3c.schema] d465f7: Modernize Python versions

[Jürgen Gmach]

  Branch: refs/heads/mod-python
  Home:   https://github.com/zopefoundation/z3c.schema
  Commit: d465f7543a5d4b18749c79b2bbffed178bca61bc
      https://github.com/zopefoundation/z3c.schema/commit/d465f7543a5d4b18749c79b2bbffed178bca61bc
  Author: Jürgen Gmach <juergen.gmach at googlemail.com>
  Date:   2020-05-14 (Thu, 14 May 2020)

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

  Log Message:
  -----------
  Modernize Python versions

- Add support for Python 3.6, 3.7, 3.8, PyPy3.

- Drop support for Python 3.3 and 3.4.

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