Method removeOrphanFiles

Removes all files and folders not found as keys of a table (used as a set!). If the provided file is a directory, it is recursively scanned for orphaned files which will be removed as well. If the directory is an orphan, it will also be removed. @param nonOrphans the table of all n

(Set<String> nonOrphans, File toDir,
                                    Set<File> preservedDirectories)