This PR has the following contributions (completing issue #34 ):
creates a session for a user, allowing the server to store the word which is sent to the client upon clicking "Begin" on /draw (I imagine this session can be leveraged by other views/endpoints too)
upon sketch submission, /submit-draw endpoint saves the sketch to app/static/sketches, and creates a database entry for the sketch
the backend catches if the user took more than the allowed time, and checks that the canvas submitted is not blank
This PR has the following contributions (completing issue #34 ):