Merge pull request #4 from kaedroho/python3

A couple of minor changes
Add prefetch_related feature for DeferringRelatedManager
Add basic prefetch_related test case
Merge branch 'artursmet-fix/add-prefetch-related'
update changelog with post-0.1 changes
Prepare 0.2 release
Added a few more queryset methods
Ensure items are ordered correctly on deserialisation
Added test for sorting with multiple keys
Don't cast to string before sorting
add explanatory comment on sort method
add changelog entry for #8
sort list after iterating over new_items has completed, not during the iteration
Merge branch 'kaedroho-ordering-fix'
Merge branch 'new-queryset-methods' of https://github.com/kaedroho/django-modelcluster into kaedroho-new-queryset-methods
add unit tests for FakeQuerySet exists(), first() and last()
changelog entry for #7
Merge branch 'kaedroho-new-queryset-methods'
prepare for 0.3 release
Make datetimes timezone aware before serialising them. Fixes #10