the latest code in master was not released

Would it be possible to publish a release and push it it to pypi? The [0.4 release](https://pypi.org/project/coreschema/0.0.4/) is from Feb 8th 2017 and does not contain [the python 3 clasifiers](https://github.com/core-api/python-coreschema/commit/494435d8fbaff12285094e99c54c38f5a1434afb) added Sept 7th 2017.