What to do to publish a new release

Ensure all notable changes are in the changelog under "Unreleased".
Execute cargo release <level> to bump version(s), tag and publish everything. External subcommand, must be installed with cargo install cargo-release.

<level> can be one of major|minor|patch. If this is the first release (0.1.0), use minor, since the version starts out as 0.0.0.
Go to the GitHub releases, edit the just-pushed tag. Copy the release notes from the changelog.