Support new binary upgrade method used by Gunicorn, since version 19.6.0. Drops support for all previous versions of Gunicorn. See commit benoitc/gunicorn418f140 for more info, thanks to Jacob Magnusson.
0.3.1
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Minor Python3 compatibility fix, thanks to Justin Locsei.
0.3.0
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Thanks to Rafael Floriano da Silva for the following: