Bump marshmallow from 2.18.1 to 3.5.0

[dependabot-preview]

Bumps marshmallow from 2.18.1 to 3.5.0.

Changelog

Sourced from marshmallow's changelog.

3.5.0 (2020-02-19)

Bug fixes:

• Fix list of nullable nested fields List(Nested(Field, allow_none=True) (1497). Because this fix reverts an optimization introduced to speed-up serialization and deserialization of lists of nested fields, a negative impact on performance in this specific case is expected.

3.4.0 (2020-02-02)

Features:

• Improve type coverage (1479). Thanks Reskov.

Bug fixes:

• Fix typing for data param of Schema.load and ValidationError (1492). Thanks mehdigmira for reporting and thanks dfirst for the PR.

Other changes:

• Remove unnecessary typecasts (1500). Thanks hukkinj1.
• Remove useless _serialize override in UUID field (1489).

3.3.0 (2019-12-05)

Features:

• fields.Nested may take a callable that returns a schema instance. Use this to resolve order-of-declaration issues when schemas nest each other (1146).

# <3.3
class AlbumSchema(Schema):
    title = fields.Str()
    artist = fields.Nested("ArtistSchema", only=("name",))
class ArtistSchema(Schema):
name = fields.Str()
albums = fields.List(fields.Nested(AlbumSchema))
>=3.3
class AlbumSchema(Schema):
title = fields.Str()
artist = fields.Nested(lambda: ArtistSchema(only=("name",)))
class ArtistSchema(Schema):
name = fields.Str()
</tr></table> ... (truncated)

Commits

• 31828bf Bump version and update changelog
• ee3b16f Merge pull request #1503 from deckar01/1497-schema-list-none
• 807af21 Bump sphinx from 2.4.1 to 2.4.2
• 29a4bf4 Merge pull request #1517 from timgates42/bugfix/typo_declared
• c106e3b Update AUTHORS.rst
• 1b4f436 Fix simple typo: declard -> declared
• e54dff8 Bump sphinx from 2.4.0 to 2.4.1
• c453e84 Add regression test for List(Nested(allow_none))
• 0249995 Revert "Optimize loading a list of Nested objects by calling load(many=True)"
• 1029039 Revert "Optimize dumping a list of Nested objects by calling dump(many=True)"
• 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.

---

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 squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor 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)
• Pull request limits (per update run and/or open at any time)
• Automerge options (never/patch/minor, and dev/runtime dependencies)
• Out-of-range updates (receive only lockfile updates, if desired)
• Security updates (receive only security updates, if desired)

[dependabot-preview]

Superseded by #107.