Upload documents as part of batches

[ghost]

Is this feasible? What would be required? The idea here is that for apps which support storing documents, users may just want to sling documents in along with other kinds of files. Exchange will need to supplement importer with a document upload capability in the near future (e.g. via a separate tab on its uploads page), but it might be nicer for users to include it all in the same importer interface.