Django commit https://github.com/django/django/commit/3647c0a49a2f4535b8a9aba40e662743e4d53e76 broke taggit. This commit fixes that. Thanks akaariai for the patch (see https://code.djangoproject.com/ticket/19399 for details).
Moved get_extra_join_sql() method into a lightweight object to prevent storing direction state in the field object -- that looked very fragile. Thanks akaariai for help
Merge pull request #4 from uruz/feature/support-django-1.6

Two new commits to support latest master in taggit