[Checkins] [zopefoundation/zope.dublincore] 8dd755: Add Python 3.6, drop Python 3.3

[GitHub]

  Branch: refs/heads/py36
  Home:   https://github.com/zopefoundation/zope.dublincore
  Commit: 8dd755f1fbd35141bbde4a01c997fd2ee3fb58f9
      https://github.com/zopefoundation/zope.dublincore/commit/8dd755f1fbd35141bbde4a01c997fd2ee3fb58f9
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2017-07-25 (Tue, 25 Jul 2017)

  Changed paths:
    A .coveragerc
    M .travis.yml
    M CHANGES.rst
    M MANIFEST.in
    M README.rst
    M docs/narrative.rst
    M setup.cfg
    M setup.py
    M tox.ini

  Log Message:
  -----------
  Add Python 3.6, drop Python 3.3

Also be sure that the doctests are run on CI and in tox. Make them
work for all versions of Python.

Use modern badge locations in README.rst since the old one was broken.