Django transaction support for Celery tasks

 django-celery-transactions holds on to Celery tasks until the current database
 transaction is committed, avoiding potential race conditions as described in
 Celery's user guide.
 .
 Features:
  * If the transaction is rolled back, the tasks are discarded. Django's
    transaction middleware does this if an exception is raised.
  * If transactions aren't being managed, tasks are sent as normal. This means
    that sending tasks from within Django's shell will work as expected, as
    will the various transaction decorators commit_manually, commit_on_success,
    etc.