v0.8.4

• #234: Window.split_window: Allow passing percent, Thank you @jinankjain!
• #289: Fix warning due to invalid escape sequences, Thank you @tirkarthi!
• #295: Publish docs via our own action
• #295: Move more packaging over to poetry, though we'll keep setup.py for the moment to ensure compatibility package maintainers.
• #295: New development instructions
• #295: Move doc/ to docs/
• #296`: CI: Test python 2.7, cache python packages, prevent running internal PRs twice