In App Scheduling

[bmino]

There is not an internal mechanism to schedule automated tasks such as auto-forfeiting and auto-challenging.

Sparc Pong will eventually migrate off of the Heroku platform and will require this feature.

Acceptance Criteria:

1. Application can schedule auto-forfeits
2. Application can schedule auto-challenges
3. Scheduling frequency is configurable via an environmental variable
4. Scheduling can be disabled entirely via an environmental variable
5. Scheduling framework can scale to accommodate additional tasks