* Adds hack/cherry_pick_list.sh to list all automated cherry picks
since the last tag.
* Adds a short python script to extract title/author and print it in
markdown style like our current release notes.
* Revises patch release instructions to use said script.
Somewhere in the last round of editing, I compressed the patch release
instructions after the release validation steps went in. They no
longer made sense because they assume some variables are set from the
previous step that you don't have set. Set them.
These instructions are now begging to be refactored between the patch
and normal releases, but I won't do that here.
This updates releasing.md with actual instructions on how to cut a
release, leaving the theory section of that document alone. Along the
way, I streamlined tiny bits of the existing process as I was
describing them.
The instructions are possibly pedantic, but should be executable by
anyone at this point, versus taking someone versant in the dark arts.
Relies on #10910. Fixes#1883.