text: Title: Migrate proplot repo to be housed under another open-source development group?
  Body: I'm wondering if the `proplot` repo here could be moved to another organization, e.g. https://github.com/matplotlib or https://github.com/pangeo-data or elsewhere that it would fit.
  
  This wonderful package now has > 1,000 stars and a lot of passionate users, but no releases or commits have been posted in 9-12 months. This is causing incompatibility issues with latest versions of core packages. I think there's a lot of eager folks submitting issues and PRs that would help to maintain a community-based version of this package! I certainly don't want to rewrite my stack to exclude `proplot`, as it has been immensely helpful in my work.
  
  I know @lukelbd is busy with a postdoc. I'm wondering if you're open to this idea! 