Bump webargs from 4.1.2 to 5.1.1

[dependabot-preview]

Bumps webargs from 4.1.2 to 5.1.1.

Changelog

Sourced from webargs's changelog.

5.1.1 (2019-01-28)

---

Bug fixes:

• Fix installing simplejson on Python 2 by
  distributing a Python 2-only wheel (:issue:363).

5.1.0 (2019-01-11)

---

Features:

• Error handlers for AsyncParser classes may be coroutine functions.
• Add type annotations to AsyncParser and AIOHTTPParser.

Bug fixes:

• Fix compatibility with Flask<1.0 (:issue:355).
  Thanks :user:hoatle for reporting.
• Address warning on Python 3.7 about importing from collections.abc.

5.0.0 (2019-01-03)

---

Features:

• Backwards-incompatible: A 400 HTTPError is raised when an
  invalid JSON payload is passed. (:issue:329).
  Thanks :user:zedrdave for reporting.

Other changes:

• Backwards-incompatible: webargs.argmap2schema is removed. Use
  webargs.dict2schema instead.
• Backwards-incompatible: webargs.ValidationError is removed.
  Use marshmallow.ValidationError instead.

.. code-block:: python

# <5.0.0
from webargs import ValidationError


def auth_validator(value):
    # ...
    raise ValidationError("Authentication failed", status_code=401)

... (truncated)

Commits

• e51110b Bump version and update changelog
• a4a52e1 Build separate wheels for Python 2 and 3
• 1928c0d Make button a reasonable size
• cb183ad Update to black's recommended flake8 config
• f7bcd2b Merge branch 'all-repos_autofix_pre-commit-autoupdate' into dev
• 6cef761 Run pre-commit autoupdate
• 7d16a45 Merge branch 'all-repos_autofix_remove-sudo' into dev
• 75de4be Remove sudo: in .travis.yml
• 1c2f034 Update pre-commit hooks; move mypy config; speed up lint env
• e33930f Merge pull request #358 from marshmallow-code/mypy
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

If all status checks pass Dependabot will automatically merge this pull request.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge
• @dependabot reopen will reopen this PR if it is closed
• @dependabot ignore this [patch|minor|major] version will close this PR and stop Dependabot creating any more for this minor/major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
• @dependabot use these labels will set the current labels as the default for future PRs for this repo and language
• @dependabot use these reviewers will set the current reviewers as the default for future PRs for this repo and language
• @dependabot use these assignees will set the current assignees as the default for future PRs for this repo and language
• @dependabot use this milestone will set the current milestone as the default for future PRs for this repo and language
• @dependabot badge me will comment on this PR with code to add a "Dependabot enabled" badge to your readme

Additionally, you can set the following in your Dependabot dashboard:

• Update frequency (including time of day and day of week)
• Automerge options (never/patch/minor, and dev/runtime dependencies)
• Pull request limits (per update run and/or open at any time)
• Out-of-range updates (receive only lockfile updates, if desired)
• Security updates (receive only security updates, if desired)

Finally, you can contact us by mentioning @dependabot.

[dependabot-preview]

Superseded by #341.