Use pytest instead of py.test per upstream recommendation, #dropthedot

[scop]

Description of changes:

http://blog.pytest.org/2016/whats-new-in-pytest-30/
https://twitter.com/hashtag/dropthedot

Merge Checklist

Put an x in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before merging your pull request.

• I have read the CONTRIBUTING doc
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[codecov-io]

Codecov Report

Merging #183 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #183   +/-   ##
=======================================
  Coverage   90.66%   90.66%           
=======================================
  Files          38       38           
  Lines        2593     2593           
=======================================
  Hits         2351     2351           
  Misses        242      242

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[andremoeller]

Hey @scop ,

Seems like I can't merge this in because it's merging in from an "unknown repository" -- do you still have a fork of this repository?

Thanks!

[scop]

I don't, but "unknown repository" shouldn't prevent merging it, several other projects have been able to do that for similar pull requests. (Such a thing results when I delete my fork before a PR from it has been merged; it's something I tend to do for various drive-by contributions.)

Anyway, if you can't merge it the usual way, you can grab a "git am"able patch at https://github.com/aws/sagemaker-python-sdk/commit/8dea405a7972425b2e46e1e17ee3780ebd7ecad7.patch

[andremoeller]

@scop ,

Got it. For some reason, I can't merge it through the UI (the button is greyed out). We'll get this in anyway though, thanks!

[laurenyu]

I was able to get the commit, but given how many commits have been pushed to master since this was opened, I've recreated this PR in #249