ndi.cloud.upload.upload_document_collection

  UPLOAD_DOCUMENT_COLLECTION - Upload a collection of documents using bulk upload

    ndi.cloud.upload.upload_document_collection(datasetId, documentList) performs 
     a bulk upload of documents to a specified dataset. It creates a ZIP archive 
     from the provided document list, retrieves a bulk upload URL for the 
     dataset, and then uploads the ZIP file to the cloud.

   IF the environment variable 'NDI_CLOUD_UPLOAD_NO_ZIP' exists and is true
     then the documents are uploaded one at a time via a slower process.

  INPUTS:
     datasetId    - (1,1) string
                    Unique identifier for the dataset to which the documents 
                    are to be uploaded (NDI Cloud dataset identifier).

     documentList - (1,:) cell
                    A cell array containing the documents to be uploaded. 
                    Each element of the cell array is a structure representing 
                    an individual document for inclusion in the upload.

  EXAMPLE:
     % Upload a collection of documents to a dataset:
     docs = {doc1, doc2, doc3};
     ndi.cloud.upload.upload_document_collection("dataset123", docs);

  See also: 
    ndi.cloud.api.documents.get_bulk_upload_url
    ndi.cloud.upload.internal.zip_documents_for_upload