Update setuptools to 38.5.0

[pyup-bot]

There's a new version of setuptools available.
You are currently using 38.4.0. I have updated it to 38.5.0

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

Changelog

38.5.0

---

• 1229: Expand imports in build_ext to refine detection of
  Cython availability.

• 1270: When Cython is available, build_ext now uses the
  new_build_ext.

38.4.1

---

• 1257: In bdist_egg.scan_module, fix ValueError on Python 3.7.

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

Happy merging! 🤖

[coveralls]

Coverage remained the same at 40.261% when pulling cf457cd on pyup-update-setuptools-38.4.0-to-38.5.0 into e11428e on master.