add app.py for Django 1.7
update README to indicate that 'syncdb' only applies to Django < 1.7
replace south migration with Django 1.7 migration
bump to Django 1.7 pip requirements (update Django version, drop south)
_meta.object_name doesn't seem to be available anymore in Django 1.7, use the content type name instead
Merge pull request #7 from JoshData/django1.7fixes

Django 1.7