Create universal wheels

[edmorley]

Previously the generated wheel was only for the version of Python under which the setup.py publish command was run, which means the Python 3 wheel was missing for the latest release:
https://pypi.python.org/pypi/coreschema/0.0.4

[jdufresne]

After #14 lands, you could include the license file in the generated wheel using the license_file in setup.cfg:

[metadata]license_file = LICENSE

See the documentation for information on this feature of wheel:

https://wheel.readthedocs.io/en/stable/#including-the-license-in-the-generated-wheel-file

This would satisfy the license's requirement:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

[edmorley]

Hi! That seems orthogonal to this PR? Wheels are already being created; this PR just makes sure they are created for both Python 2 and 3, not just one of Python {2, 3}.

As such, it's probably best as a new issue (or a comment on #14), rather than here.

[edmorley]

@tomchristie, don't suppose you could merge this? :-)

[edmorley]

Ping? :-)

[lovelydinosaur]

Refs core-api/python-openapi-codec#47