[Checkins] [zopefoundation/zope.exceptions] 6e5e3c: Add tox -e flake8, fix flake8 errors

[Marius Gedminas]

  Branch: refs/heads/flake8
  Home:   https://github.com/zopefoundation/zope.exceptions
  Commit: 6e5e3cdead491f6066a0da8c4a5e988a8e7f8e6f
      https://github.com/zopefoundation/zope.exceptions/commit/6e5e3cdead491f6066a0da8c4a5e988a8e7f8e6f
  Author: Marius Gedminas <marius at gedmin.as>
  Date:   2020-04-10 (Fri, 10 Apr 2020)

  Changed paths:
    M setup.py
    M src/zope/__init__.py
    M src/zope/exceptions/__init__.py
    M src/zope/exceptions/exceptionformatter.py
    M src/zope/exceptions/log.py
    M src/zope/exceptions/tests/test_exceptionformatter.py
    M src/zope/exceptions/tests/test_log.py
    M tox.ini

  Log Message:
  -----------
  Add tox -e flake8, fix flake8 errors