When creating a new filter set iterate the filters and apply the parent attribute so the field has a reference to the viewset
Add MethodFilter which will allow for action to be a string and call a class method of the filterset it exists within
* Documentation for the method filter
Tests for the method filter
Use six iteritems to be compatable with python3
Use six to determine the proper text types, unicode no longer exists in python 3
Fixes a bug with python 2.6 deepcoy, see http://bugs.python.org/issue1515
Wrong copy import
Merge branch 'develop' of github.com:jaredlewis/django-filter into jaredlewis-develop
Merge pull request #165 from carltongibson/feature-MethodFilter

Feature:  Adds `MethodFilter` with tests and docs