Dumping to zip file repeatedly appends to the zip file

[kriston]

Dumping to zip file repeatedly appends to the zip file one file at a time as they are downloaded. Appending zip files is very inefficient compared to creating the zip file at the end of the download operation.

It will be more useful to just download the files and leave them where they land on the filesystem. Another useful option would be to just download the files directly and don't zip them at all.