R1:c585f97e90d2

Remove horrible old repository edit controller

Summary:
Ref T2231. I didn't port these options over, so they're still supported but have no edit UI:

- Pull Frequency (confusing/not useful, I think?)
- Default Owners Path (probably used only by Facebook and only in the E repository)
- Show user in public repository URL (probably mostly obsolete with hosting?)

We can add those back if users notice, but they seem like the three least useful options so I'm going to see if we can get away with removing…