More new-install UX stuff. If you haven't completed all the setup to get Phabricator ready to host repos (including configuring phd.user), creating a new repo leaves things in a weird state where there are no URIs and no obvious explanation about how to fix it. It's also frustrating because the only Diffusion documentation linked to from the "Configuration Guide" diviner page is this page, which doesn't contain the needed info: https://secure.phabricator.com/book/phabricator/article/diffusion/

The actual docs are here: https://secure.phabricator.com/book/phabricator/article/diffusion_hosting/

I'd suggest doing at least one of these:

• Add "Missing phd.user" as a setup issue. Might be a blunt instrument for installs that only observe external repos?
• Mention the lack of phd.user in the Diffusion "New Repo" page (or possibly show a warning when trying to activate a repo with no configured URIs and no phd.user).

See screenshot of the resulting repo: