Provide a way to specify unique files in a review be treated as versions of the same file.

This would also be helpful for files that were uploaded directly from the web interface (no source control integration, etc.); if you upload your revised version from a different directory then it appears as two different files with the same name. Doesn't sound like it would happen often but I have done this before, and recently someone else in my group did the same thing.

Update on Sept 8/2016 - it appears that this is no longer the case for files uploaded from the web interface, it appears this must have been changed in one of the Collaborator v9 releases.