Update werkzeug to 0.15.3

[pyup-bot]

This PR updates Werkzeug from 0.15.2 to 0.15.3.

Changelog

0.15.3

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

Released 2019-05-14

-   Properly handle multi-line header folding in development server in
 Python 2.7. (:issue:`1080`)
-   Restore the ``response`` argument to :exc:`~exceptions.Unauthorized`.
 (:pr:`1527`)
-   :exc:`~exceptions.Unauthorized` doesn't add the ``WWW-Authenticate``
 header if ``www_authenticate`` is not given. (:issue:`1516`)
-   The default URL converter correctly encodes bytes to string rather
 than representing them with ``b''``. (:issue:`1502`)
-   Fix the filename format string in
 :class:`~middleware.profiler.ProfilerMiddleware` to correctly handle
 float values. (:issue:`1511`)
-   Update :class:`~middleware.lint.LintMiddleware` to work on Python 3.
 (:issue:`1510`)
-   The debugger detects cycles in chained exceptions and does not time
 out in that case. (:issue:`1536`)
-   When running the development server in Docker, the debugger security
 pin is now unique per container.

Links

• PyPI: https://pypi.org/project/werkzeug
• Changelog: https://pyup.io/changelogs/werkzeug/
• Homepage: https://palletsprojects.com/p/werkzeug/

[coveralls]

Coverage remained the same at 86.879% when pulling bb5777c on pyup-update-werkzeug-0.15.2-to-0.15.3 into d7af8da on master.

[pyup-bot]

Closing this in favor of #135