v1.9.0rc1

Minor Changes

• Adopt PEP-621 (#198) @ssbarnea
• Refactor testing (#194) @ssbarnea
• Remove python3.6 support (#190) @dvzrv

Bugfixes

• Ensure we require py37 or newer (#199) @ssbarnea
• Enable prettier (#197) @ssbarnea
• Test with py36 and py37 (#195) @ssbarnea
• Fix license headers in source files (#192) @leifwalsh
• Only match URLs on word boundaries; add # (#187) @hellux
• Update build-system requirements (#189) @dvzrv
• Add support for python 3.11 (#183) @ssbarnea
• Add support for python 3.10 (#182) @ssbarnea