* First RQScheduler prototype
* WIP job scheduling
* Fixed Python 2.7 tests
* Added ScheduledJobRegistry.get_scheduled_time(job)
* WIP on scheduler's threading mechanism
* Fixed test errors
* Changed scheduler.acquire_locks() to instance method
* Added scheduler.prepare_registries()
* Somewhat working implementation of RQ scheduler
* Only call stop_scheduler if there's a scheduler present
* Use OSError rather than ProcessLookupError for PyPy compatibility
* Added `auto_start` argument to scheduler.acquire_locks()
* Make RQScheduler play better with timezone
* Fixed test error
* Added --with-scheduler flag to rq worker CLI
* Fix tests on Python 2.x
* More Python 2 fixes
* Only call `scheduler.start` if worker is run in non burst mode
* Fixed an issue where running worker with scheduler would fail sometimes
* Make `worker.stop_scheduler()` more resilient to errors
* worker.dequeue_job_and_maintain_ttl() should also periodically run maintenance tasks
* Scheduler can now work with worker in both burst and non burst mode
* Fixed scheduler logging message
* Always log scheduler errors when running
* Improve scheduler error logging message
* Removed testing code
* Scheduler should periodically try to acquire locks for other queues it doesn't have
* Added tests for scheduler.should_reacquire_locks
* Added queue.enqueue_in()
* Fixes queue.enqueue_in() in Python 2.7
* First stab at documenting job scheduling
* Remove unused methods
* Remove Python 2.6 logging compatibility code
* Remove more unused imports
* Added convenience methods to access job registries from queue
* Added test for worker.run_maintenance_tasks()
* Simplify worker.queue_names() and worker.queue_keys()
* Updated changelog to mention RQ's new job scheduling mechanism.
Selwin Ong