zip a folder rather than zip files

[tilfischer]

Chemotion Repository allows users to download analytical data files (e.g. for 1H NMR spectroscopic data a PNG, a JCAMP-DX file and a ZIP of NMR data in Bruker format) wrapped as ZIP files. Each ZIP file also contains a dataset_description.txt, which provides information on the dataset name, instrument, description and a list of files within this dataset including their checksum.

Extracting several downloaded dataset (e.g. 1H, 13C, IR and MS of CRS-26183) at once will ask the users whether the dataset_description.txt of the 1H NMR dataset shall be overwritten with the dataset_description.txt of the 13C NMR dataset and so forth.

A workaround is to unzip to */ . However, Chemotion Repository could avoid any of such issues if the downloaded zipped datasets would be ZIPs of folders, having the name of the dataset, rather than ZIP files of files.

[tilfischer]

Also connected to #32.