* TicketField will only generate a new ticket value when the field value is None (potentially breaking change)
0.7.2
* Ensure that we only try to set the rollback status if the connection is inside of an atomic block.
0.7.1
* Fixes [6](https://github.com/streeter/django-ticketing/issues/6) by marking the database as not needing a rollback after catching an exception to retry generating a ticket.
0.7.0
* Requires Django 1.6 or higher * Adds a single retry to generating a ticket in the case of a database `OperationError` (ie. deadlock).