Refactored sorting_filters into a tuple and moved logic for retrieving sorting filters into the sort_view versus changelist_view.
Updated readme.
Updated sample project to leverage new sorting_filters on Person model and admin.
Removed custom change list template for Person admin.
Merge pull request #77 from iambrandontaylor/multi-sorting-groups

Refactored sorting_filters into a tuple and moved logic for retrieving s...