add python 3 to setup.py classifiers

this should show up on pypi as python3 ready,
but only after a new release is done
maintain compatibility with Python 2.6
Merge pull request #75 from gertingold/py26compat

maintain compatibility with Python 2.6
correct import deprecated since Django 1.4
Merge pull request #77 from gertingold/deprecated_import

fix(docs): show up to date import in example
Support non-int primary keys
Django's HttpResponse object has deprecated the mimetype kwarg in 1.7, now content_type
use match instead of repr
Merge pull request #85 from camillobruni/develop

Fix issue 58 and pull request 76
Merge pull request #82 from squidsoup/develop

Django's HttpResponse object has deprecated the mimetype kwarg in 1.7
Merge pull request #78 from AlexHill/patch-1

Support non-int primary keys
update version number
extra thanks to brian in docs
Merge branch 'release/1.3.5'