Organization GitHub Pages site for AMMnet. Its only job right now is forwarding
old https://ammnet.github.io/ammnet-hackathon/... links to the same path on
https://labs.ammnet.org, which is served from
AMMnet/skills-lab.
404.html does the forwarding: GitHub Pages serves it for any path with no
matching file. Do not add a custom domain to this repository, and do not create
a repository named ammnet-hackathon (that would break GitHub’s redirects
from the old repository name to AMMnet/skills-lab).