Add section headers similar to the 3.2 release notes and move each
individual bullet into an appropriate section. Revise and consolidate
some bullets covering related areas.
Move all development release notes into a new version-specific document:
tail -q -n +3 Help/release/dev/* > Help/release/3.3.rst
git rm -- Help/release/dev/*
except the sample topic:
git checkout HEAD -- Help/release/dev/0-sample-topic.rst
Reference the new document from the release notes index document.
Add a title and intro sentence to the new document by hand.