show upload progress on import course view

STUD-2017

@nasthagiri Gunicorn 0.17.4 immediately terminates the process on timeout while 19.1.0 calls sys.exit() which executes any finally clauses and so lets the cleanup happen. We will not merge this version update with this PR but are going to ask devops to do so separately.

@zubair-arbi Did you create a ticket for it?