Release Checklist

Update CHANGELOG
Verify that all CI tests pass for current master
Tag the release, and push to Github
Wait for tag CI to complete
Download assets from snapshots.mitmproxy.org
Create release notice on Github
Upload wheel to pypi (twine upload wheelname)
Update docker-releases repo
- Create a new branch based of master for major versions.
- Add a commit that pins dependencies like so: 3d6a9989fd. The requirements can be obtained by creating a fresh venv, pip-installing the new wheel in there, and then running pip freeze.
Update latest tag on https://hub.docker.com/r/mitmproxy/mitmproxy/~/settings/automated-builds/
Bump the version in https://github.com/mitmproxy/mitmproxy/blob/master/mitmproxy/version.py and update https://github.com/mitmproxy/mitmproxy/blob/master/mitmproxy/io_compat.py in the next commit