R1:b57b72368c3c

Move "Remote URI" to modern repository editor thing

Summary:
Ref T2231. Allows you to edit the remote URI and credentials.

This is a little bit funky because I'm reusing some of the pages on the new (not-yet-hooked-up) create form. Specifically, it had pages like this:

- Repo Type
- Name/Callsign/Remote
- Auth
- Done

I split "Name/Callsign/Remote" into "Name/Callsign" and "Remote", then when editing the remote I just take you through "Remote" and "Auth" and then back. This lets us reuse the…