Changelog - Hand Curate vs Autogenerate vs Require on PRs

[ianhi]

At the widgets meeting on March 4 there was discussion of autogenerating a changelog or perhaps enforcing manual curation on PRs.

jupyter-widgets/team-compass#1 (comment)

Opening this issue to discuss what if we should:

1. Keep the current manual curation at release time
2. Move to some sort of autogenerating changelog
3. Require PRs to include adding a brief description to changelog (what matplotlib does)

[jasongrout]

For reference, here is what I've been doing, at least for getting a changelog curation for recent RCs, building on our experience doing the changelog for jlab: https://ipywidgets.readthedocs.io/en/latest/dev_release.html#changelog

[jasongrout]

One issue is that often the PRs are not assigned to the correct milestone, etc., so often there is a manual curation step just for that. We could also automate some of that (check where a commit was merged into a tree, and make sure the PR is assigned to the corresponding milestone).