return session id for upload methods

[rjanjua]

User Story
As a user
I want to be able to check the status of the session I just uploaded
So that I know my upload was successful

Relevant Links

Acceptance Criteria

• all upload methods return session id
• upload methods return details of session success

[elundaeva]

+1, this was quite a blocker in the Cambridge University trial. Our contact there was trying to upload 2K files, but only PDF files were coming through, no TXTs. The session status looked as if all went well, and it was quite frustrating for the customer to not see in the outputs what files failed and why. Rohan had to investigate further to be able to unblock, but ideally the customers would be able to troubleshoot such upload issues themselves based on error messages.

[ArzelaAscoIi]

@rjanjua So this means that in addition to the returned upload summary we need to add the session_id to the S3UploadSummary object, right ?

We would need to extend the implementation of this PR, right? #101