Update raven to 6.6.0

[pyup-bot]

This PR updates raven[flask] from 6.3.0 to 6.6.0.

Changelog

6.6.0

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* [Core] Add trimming to breadcrumbs.
* [Core] Improve host message at startup.
* [Core] Update pytest to work on other environments

6.5.0

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* [Core] Fixed missing deprecation on `processors.SanitizePasswordsProcessor`
* [Core] Improve exception handling in `Serializer.transform`
* [Core] Fixed `celery.register_logger_signal` ignoring subclasses
* [Core] Fixed sanitizer skipping `byte` instances
* [Lambda] Fixed `AttributeError` when `requestContext` not present

6.4.0

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* [Core] Support for defining `sanitized_keys` on the client (pr/990)
* [Django] Support for Django 2.0 Urlresolver
* [Docs] Several fixes and improvements

Links

• PyPI: https://pypi.python.org/pypi/raven
• Changelog: https://pyup.io/changelogs/raven/
• Repo: https://github.com/getsentry/raven-python

[coveralls]

Coverage remained the same at 84.842% when pulling 903292b on pyup-update-raven-6.3.0-to-6.6.0 into 3157487 on master.

[stephendonner]

r+