Refactored behaviors
Refactored behaviors

Refactoring of Behaviors to generalize settings merging and field adding.  Merging is now defined on the base behavior class and works by looking through the mro to find which behaviors a model inherits from, and then passing the settings down, starting at the top of the mro.  Field adding is still handled by each individual behavior model as well.  After determining which behaviors a model has, each of those base behaviors has it's `add_fields_to_child` method called on the child model.

fusionbox/django-argonauts