Uploading Program or Data with directory structure

When you upload a scoring program or an ingestion program in your Resources, you can either zip it with the directory structure:

scoring_program.zip
|-- scoring_program/
|---|-- score.py
|---|-- metadata

or without the directory structure:

scoring_program.zip
|-- score.py
|-- metadata

I think that right now only the second option works. We should make this more robust.