Error in datasets extract makes diagram generation fail

[frmichel]

Script get_data.py starts by getting datasets list from https://lod-cloud.net/extract/datasets.

This file contains the error "keywords" : "", for dataset " https://data.bioontology.org/ontologies/BOF/download?apikey=8b5b7825-538d-40e0-9e9e-5ab9274a9aeb&download_format=rdf". This should be an empty array.

I think this format issue is NOT fixed by script get_data.py that produces a file with the same issue. As a result lod-cloud-draw fails and returns the laconic error "Data contains a JSON error".

I found it by replacing the error message in src/main.rs#208 with {panic!("{}, err)}.