Bump version to 1.20.0

Bump version to 1.19.1

Fix metadata formatting (#220)

Add 'Typing :: Typed' classifier

Follow-up on #190, see https://pypi.org/classifiers/.

Cut version 1.18.0

bump for 1.17.12 release

Forgot to stamp 1.17.10, stamp 1.17.11

thanks to #181, looks like I forgot to push a version
change commit before stamping, my master branch was 1
commit ahead, 1.17.10 was released to pypi, but the
code contents of github.com have read 1.17.9, this is
also bad for sphinx!

Anyway, we release 1.17.11 to avoid any discrepancies

Merge pull request #178 from maybeetree/tmux_arrow_fix

Fix shift+arrow keys for tmux

Fixes and non-critical testing for Python 3.10-dev (#177)

Merge pull request #173 from jquast/better-sdist

Reduce documentation garbage in sdist, regression from #161