Update django-pandas to 0.4.4

[pyup-bot]

There's a new version of django-pandas available.
You are currently using 0.4.1. I have updated it to 0.4.4

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

Changelog

0.4.4

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• The verbose argument now handles more use cases (Thanks to henhuy and
  Kevin Abbott)
• Corece float argument add to to_timeseries() method (Thanks Yousuf Jawwad)

0.4.3

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• Fix doc typos and formatting
• Prevent column duplication in read_frame (Thanks Kevin Abbott)

0.4.2

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• Compatibility with pandas 0.20.1
• Support for Python 2.7 and 3.5 with Django versions 1.8+
• Suport for Python 3.6 and Django 1.11
• We still support legacy versions (Python 2.7 and Django 1.4)

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

Happy merging! 🤖