3.1.0rc0

What's Changed

• black edits by @cadenmyers13 in #118
• add flake8, pre-commit, pyproject files by @cadenmyers13 in #121
• tests by @sbillinge in #123
• add environment.yml by @sbillinge in #130
• Cookie by @sbillinge in #179
• use download for document files by @Tieqiong in #180

Full Changelog: 3.0.5...3.1.0rc0