change FilterSet to invoke form errors and skip filtering on invalid data, returning empty queryset with strict mode
Add `FilterSet.get_order()` method for very custom ordering
Fixed support for newer wheel versions.
Disable python 2.6 on tests against Django master.
Fixed tests for Django 1.6/1.7.
Fix a typo in the get_order docs

Ordering people by name should be last name, first name; not last name,
last name.
Rename FilterSet.get_order to get_order_by

As requested in #106
Update docs to reflect renamed get_order_by method
change default value for strict to True, and hopefully made the code for filtering with invalid values clearer (also removed _SENTINEL)
- need to differentiate between actual 'None' value and a ValidationError
- grab order_by value in for loop, avoids double lookup and eliminates need for get_value function
fix a few tests due to defaulting strict = True
Merge branch 'develop' into nkryptic-issue-84
Merge pull request #108 from apollo13/issue-84

Issue 84
keep example FilterSet class name consistent
explain the "strict" FilterSet option in the docs...created subsection to make it clearer it isn't a Meta option
Merge pull request #109 from whitews/develop

update docs to explain 'strict' FilterSet option
Add descending field options to order_by when using order_by=True

Fixes #91
Fix (fltr.name or f) in string format.
User friendly descending labels

and switched from list comprehension to regular loop for readability.
Translation marker for '%s descending'.