Update flake8 to 3.7.3

[pyup-bot]

This PR updates flake8 from 3.6.0 to 3.7.3.

Changelog

3.7.3

-------------------

You can view the `3.7.3 milestone`_ on GitLab for more details.

Bugs Fixed
~~~~~~~~~~

- Fix imports of ``typing`` in python 3.5.0 / 3.5.1 (See also `GitLab!294`_,
`GitLab498`_)

- Fix ``flake8 --statistics`` (See also `GitLab!295`_, `GitLab499`_)

- Gracefully ignore ``flake8-per-file-ignores`` plugin if installed (See also
`GitLab!297`_, `GitLab495`_)

- Improve error message for malformed ``per-file-ignores`` (See also
`GitLab!298`_, `GitLab489`_)


.. all links
.. _3.7.3 milestone:
 https://gitlab.com/pycqa/flake8/milestones/26

.. issue links
.. _GitLab489:
 https://gitlab.com/pycqa/flake8/issues/489
.. _GitLab495:
 https://gitlab.com/pycqa/flake8/issues/495
.. _GitLab498:
 https://gitlab.com/pycqa/flake8/issues/498
.. _GitLab499:
 https://gitlab.com/pycqa/flake8/issues/499

.. merge request links
.. _GitLab!294:
 https://gitlab.com/pycqa/flake8/merge_requests/294
.. _GitLab!295:
 https://gitlab.com/pycqa/flake8/merge_requests/295
.. _GitLab!297:
 https://gitlab.com/pycqa/flake8/merge_requests/297
.. _GitLab!298:
 https://gitlab.com/pycqa/flake8/merge_requests/298

3.7.2

-------------------

You can view the `3.7.2 milestone`_ on GitLab for more details.

Bugs Fixed
~~~~~~~~~~

- Fix broken ``flake8 --diff`` (regressed in 3.7.0) (See also `GitLab!292`_,
`GitLab490`_)

- Fix typo in plugin exception reporting (See also `GitLab!275`_,
`GitLab491`_)

- Fix ``AttributeError`` while attempting to use the legacy api (regressed in
3.7.0) (See also `GitLab!293`_, `GitLab497`_)

.. all links
.. _3.7.2 milestone:
 https://gitlab.com/pycqa/flake8/milestones/25

.. issue links
.. _GitLab490:
 https://gitlab.com/pycqa/flake8/issues/490
.. _GitLab491:
 https://gitlab.com/pycqa/flake8/issues/491
.. _GitLab497:
 https://gitlab.com/pycqa/flake8/issues/497

.. merge request links
.. _GitLab!292:
 https://gitlab.com/pycqa/flake8/merge_requests/292
.. _GitLab!275:
 https://gitlab.com/pycqa/flake8/merge_requests/275
.. _GitLab!293:
 https://gitlab.com/pycqa/flake8/merge_requests/293

3.7.1

-------------------

You can view the `3.7.1 milestone`_ on GitLab for more details.

Bugs Fixed
~~~~~~~~~~

- Fix capitalized filenames in ``per-file-ignores`` setting (See also
`GitLab!290`_, `GitLab488`_)

.. all links
.. _3.7.1 milestone:
 https://gitlab.com/pycqa/flake8/milestones/24

.. issue links
.. _GitLab488:
 https://gitlab.com/pycqa/flake8/issues/488

.. merge request links
.. _GitLab!290:
 https://gitlab.com/pycqa/flake8/merge_requests/290

3.7.0

-------------------

You can view the `3.7.0 milestone`_ on GitLab for more details.

New Dependency Information
~~~~~~~~~~~~~~~~~~~~~~~~~~

- Add dependency on ``entrypoints`` >= 0.3, < 0.4 (See also `GitLab!264`_,
`GitLab!288`_)

- Pyflakes has been updated to >= 2.1.0, < 2.2.0 (See also `GitLab!283`_,
`GitLab!285`_)

- pycodestyle has been updated to >= 2.5.0, < 2.6.0 (See also `GitLab!287`_)

Features
~~~~~~~~

- Add support for ``per-file-ignores`` (See also `GitLab!259`_, `GitLab156`_,
`GitLab!281`_, `GitLab471`_)

- Enable use of ``float`` and ``complex`` option types (See also `GitLab!261`_,
`GitLab452`_)

- Improve startup performance by switching from ``pkg_resources`` to
``entrypoints`` (See also `GitLab!264`_)

- Add metadata for use through the `pre-commit`_ git hooks framework (See also
`GitLab!268`_, `GitLab!284`_)

- Allow physical line checks to return more than one result (See also
`GitLab!269`_)

- Allow `` noqa:X123`` comments without space between the colon and codes
list (See also `GitLab!273`_, `GitLab470`_)

- Remove broken and unused ``flake8.listen`` plugin type (See also
`GitLab!274`_, `GitLab480`_)

.. all links
.. _3.7.0 milestone:
 https://gitlab.com/pycqa/flake8/milestones/23
.. _pre-commit:
 https://pre-commit.com/

.. issue links
.. _GitLab156:
 https://gitlab.com/pycqa/flake8/issues/156
.. _GitLab452:
 https://gitlab.com/pycqa/flake8/issues/452
.. _GitLab470:
 https://gitlab.com/pycqa/flake8/issues/470
.. _GitLab471:
 https://gitlab.com/pycqa/flake8/issues/471
.. _GitLab480:
 https://gitlab.com/pycqa/flake8/issues/480

.. merge request links
.. _GitLab!259:
 https://gitlab.com/pycqa/flake8/merge_requests/259
.. _GitLab!261:
 https://gitlab.com/pycqa/flake8/merge_requests/261
.. _GitLab!264:
 https://gitlab.com/pycqa/flake8/merge_requests/264
.. _GitLab!268:
 https://gitlab.com/pycqa/flake8/merge_requests/268
.. _GitLab!269:
 https://gitlab.com/pycqa/flake8/merge_requests/269
.. _GitLab!273:
 https://gitlab.com/pycqa/flake8/merge_requests/273
.. _GitLab!274:
 https://gitlab.com/pycqa/flake8/merge_requests/274
.. _GitLab!281:
 https://gitlab.com/pycqa/flake8/merge_requests/281
.. _GitLab!283:
 https://gitlab.com/pycqa/flake8/merge_requests/283
.. _GitLab!284:
 https://gitlab.com/pycqa/flake8/merge_requests/284
.. _GitLab!285:
 https://gitlab.com/pycqa/flake8/merge_requests/285
.. _GitLab!287:
 https://gitlab.com/pycqa/flake8/merge_requests/287
.. _GitLab!288:
 https://gitlab.com/pycqa/flake8/merge_requests/288

Links

• PyPI: https://pypi.org/project/flake8
• Changelog: https://pyup.io/changelogs/flake8/
• Repo: https://gitlab.com/pycqa/flake8

[pyup-bot]

Closing this in favor of #567