Ability to change hackathon settings and questions during run-time

[seanjparker]

The current design of the hs_applications platform means that the hackathon settings (start_time, end_time etc) and the hackathon form questions are loaded when the service is started.

A ease-of-use improvement would be to have an admin page where these settings could be altered while the service is running. I think the way this should be approached is to alter the hackathon.json and questions.json directly. Provide an admin form where we can edit the settings and the new settings are written to the files