open_archive only top folder for zipfile

[ghost]

1. tar.gz and zip files quite often contain nested archives. tarfile recursively extracts files, zipfile doesn't and requires an extra step. This leaves the artifact contents incompletely extracted.
2. In either case folder and final file locations aren't clear by default.
3. We may want to log all the nested file contents as artifacts, particularly if they are tables, if they are layered images (image_blue, image_red, image_green) we may want to generate a metadata description summarizing these findings... (idea: if 3. is the case, and the files represent keys and data, normalized database tables, the extract process might also recommend possible joins)