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*Bugfix:*
* Fix hook registration on custom implementations while inheriting
:class:`~xworkflows.WorkflowEnabled`.
*New:*
* Add support for Python 2.6 to 3.2
*Backward incompatible:*
* The string representation of :class:`~xworkflows.base.State` and :class:`~xworkflows.base.StateWrapper`
now reflects the state's name, as does their :meth:`unicode` representation in Python 2.X.