Allow removing "recent files" entries

[HikeAndMap]

Adding the possibility to clean the "recent" files .. as I quite often work with "temporary" files downloaded and exported through JOSM.

But then I have non-existing-anymore files listed there so it would be great if we could wipe it empty from time to time to make selection of valid files easier

[tordanik]

I agree that some way of removing temporary/deleted files from the list would be useful. Marking this as a feature request.