• Big changes to simplify the way Huey is instantiated. No changes should
  be necessary if already using RedisHuey.
• Refactored the storage APIs and simplified the public interface. There is
  now a single object, whereas before there were 4 components (queue, result
  store, scheduler and event emitter).
• Added methods for retrieving and introspecting the pending task queue, the
  schedule, results, and errors.
• Errors can now be stored, in addition to regular task results.
• Added metadata methods for tracking task execution, errors, task duration,
  and more. These will be the building blocks for tools to provide some
  insight into the inner-workings of your consumers and producers.
• Many new events are emitted by the consumer, and some have parameters. These
  are documented here.