Add Image Diff options in Pull Request Diff view (#14450)

Implemented GitHub style image diff

options/locale/locale_en-US.ini

@@ -1854,6 +1854,9 @@ diff.review.approve = Approve
 diff.review.reject = Request changes
 diff.committed_by = committed by
 diff.protected = Protected
+diff.image.side_by_side = Side by Side
+diff.image.swipe = Swipe
+diff.image.overlay = Overlay
 
 releases.desc = Track project versions and downloads.
 release.releases = Releases