Merge branch 'update-mypy-types'

Merge branch 'improve-middleware-correctness'

Ensure statsd tags are strings

Fix statsd plugin README

Fix upload script

Merge pull request #102 from thread/statsd-plugin

StatsD plugin

Merge branch 'fix-readme-on-pypi'

Merge branch 'test-more-pythons'

Improve the error message when removing states still in use

Whitespace