bump version to 0.19.0

Bump version to 0.18.0

Bump version to 0.18.3

Bump version to 0.18.2.

Bump version to 0.18.1 w/ updated README.md.

Bump version to v0.18.0 - First pyfloyd release.

Bump version to v0.17.2.

Bump version to v0.17.1 so we can push a package to PyPI.

Bump version to v0.17.0 for the now-empty repo.

Release version v0.16.0.