convert/bzr: correctly handle divergent nested renames (issue3089) With renames like: a -> b a/c -> a/c We were ignoring or duplicating the second one instead of leaving files unchanged or moving them to their proper destination only. To avoid this, we process the files in reverse lexicographic order, from most to least specific change, and ignore files already processed. v2: - Add a test - Change "reverse=1" into "reverse=True"