Issue title: automate more of release process
 Issue body: I'm getting pretty tired of our manually-intensive release process. At a minimum, something ought upload signatures etc. I looked around, and (githubrelease)[https://pypi.org/project/githubrelease/] looks like it might be just the ticket.
 Comments: 
 Comment 0: I'm now doing everything up through actual (distro-specific) packaging. That's a pretty good step forward.

https://www.youtube.com/watch?v=8UGtlUMMkOU
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