Handle renamed files

[jsoref]

Improve handling for renamed files

Currently when I click on a png file that's listed as R (which is apparently a Renamed file), I get:

Ideally:

• I should be able to view the file locally and have a thing that tells me its renamed at the top/bottom of the view
• I should be able to add comments on the file change (as I can in the GitHub web ui)

In the interim, it'd be nice if the floating message at the bottom said "because it's a rename" -- so it's clear it's because of the R and not, e.g. because it's a .png.

[alexr00]

I'm not able to repro this with a rename. Do you have a public PR I could look at that shows this issue?

[jsoref]

The repository in question is/was https://github.com/check-spelling-sandbox/GraphScope/
check-spelling-sandbox/GraphScope@1f8d832 is a commit with the change.

[alexr00]

I can repro, thanks!

[roblourens]

This is working for a text file, but not an image

In this PR that just does a basic rename of two files

https://github.com/roblourens/testrepo/pull/13