Collection copying

[mizdebsk]

We need a way to copy collections, for example when branching happens. Otherwise:

• people are confused ("koschei shows me rebuilds for rawhide, f26 and epel7. how so trojita rebuild works in rawhide and epel7 but not in f26?")
• new fedmsg messages are sent "pkg started to fail" even for long-time failing pkgs
• resolver processes all builds again

[voxik]

In this context, I especially wonder, why Rawhide is simply not Rawhide and it is Fxx? When I open F27 repo now, I see just 2 weeks history. I'd be less surprised to see this behavior for F26 after branching, since F26 is fresh branch ...

[mizdebsk]

The reason is mostly consistency with Koji - there are no "rawhide" build tags in Koji, all tags are named fNN-something. But I definitely agree that history should be preserved and this issue is about fixing this problem.

[mizdebsk]

Sending fedmsgs can't be undone, but it may be possible to restore history post-factum.