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* Moved to Haystack GitHub org: https://github.com/django-haystack/celery-haystack
* Fix handling the default Haystack backend alias, making it a list.
* Added ``CELERY_HAYSTACK_QUEUE`` setting to define which Celery queue to use.
* Added ``CELERY_HAYSTACK_COUNTDOWN`` setting to define when to start the
indexing task after initially creating it.
* Stop returning after after enqueing in the Haystack router to support
multple routers.
* Optionally support using django-transaction-hooks for improved transaction
handling.
* Instantiate update task class correctly.
* Use Celery's task logger utility function.