Release to pypi

[davidread]

It would be helpful if you are able to release another version to pypi. The current latest dates from July 2016.

Personally I could do with this fix:
#301
coming through into my CI.

[gsnedders]

With a huge thanks to @willkg for making everything happen, 1.0 is now on PyPI.

[hugovk]

The 1.0 milestone may be closed now:

• https://github.com/html5lib/html5lib-python/milestone/1