Update flask-mongoengine to 0.9.2

[pyup-bot]

There's a new version of flask-mongoengine available.
You are currently using 0.8.0. I have updated it to 0.9.2

These links might come in handy: PyPI | Changelog | Repo

Changelog

0.9.1

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• Fixed setup.py for various platforms (298).
• Added Flask-WTF v0.14 support (294).
• MongoEngine instance now holds a reference to a particular Flask app it was initialized with (261).

0.9.0

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• BREAKING CHANGE: Dropped Python v2.6 support

0.8.2

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• Fixed relying on mongoengine.python_support.
• Fixed cleaning up empty connection settings 285

0.8.1

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• Fixed connection issues introduced in 0.8
• Removed support for MongoMock

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖

[noirbizarre]

Merged in #812