Merge branch 'main' of git.adrian.geek.nz:/srv/git/haskell-stylist into main
Remove Stylist-Traits APIs from Stylist Core, leaving backwards-compatible stubs.
Add hook for callers to run their own tests against attributes.
Parse namespace selectors.
Improve documentation, release version 1.2
Rework psuedoelement infrastructure so they can be their own boxes.
Test/fix parsing of psuedoclasses/elements.
Add support for psuedoelements/classes.
Improve code cleanliness to avoid future bugs.
Switch to new namespace for consistency with other modules like css-syntax.