GUI: Build Entry comparison page (Snapshots only?)

[tangkong]

No description provided.

[tangkong]

This looks like it relies on #9 , @shilorigins did you already start work on the client-level comparison function? If not I can take a crack at it

[shilorigins]

I haven't. But this issue seems like it overlaps with the restore page functionality of comparing snapshots. That one is focused on PV values, is this one focused on metadata or something other than the contained PVs?

[tangkong]

At the very least, I think that this comparison should happen at the client level, rather than in the UI. Ideally the UI calls this client function, and picks the data that it cares about.

If we sequester this functionality inside the UI, we won't be able to access it from other apps that only use the client.

[shilorigins]

Sure, and I can write the snapshot portion of the client method since I'll use it for the restore page. But I was also thinking about how this comparison page will handle snapshots, because of that overlap between the pages.

[tangkong]

I want to take a look at this for comparing arbitrary Entry's, I think a complete treatment of this probably looks pretty different from the existing snapshot restore page