Operation: Change copy and move operation to work with multiply source_path for expanded directory

Operation: Change copy and move operation to work with multiply source_path for expanded directory
"source_path = None" can reduce memory consumption?
i do source_path = source_path or self._source_path https://github.com/MeanEYE/Sunflower/pull/20/files#diff-85ccebe5e0495b1e8a77480233cab440R681 for backward compatibility