Allow to provide an array to the Batch.upload() method

Currently when uploading blobs, the Batch.upload() method accepts:

• A single file Batch.upload(blob)
• Several files that have to be hardcoded Batch.upload(blob1, blob2, blob3)

=> This behavior makes things difficult when it comes to browsing a folder and adding files to the batch.

=> An improvement would be to allow passing an array to the upload method: Batch.upload(myArray) so that you could do the following:

• Browse a folder
• Add the files in an array
• Add the files to the batch in a single call by providing the array