Arrows to next image row/column from individual image viewer

[julie-puckett]

When I'm in the front end viewer for individual images, I'd like to be able to quickly switch to the image in the next row or column (if multiple image columns) without needing to close the viewer and then click the image I want.

Is there a way to add left/right and up/down arrows, or hotkeys to enable this? It would be great if the zoom settings are maintained when switching images, too.

[dsblank]

That would be great! PRs accepted!