Update trove classifiers
Update trove classifiers

This should help reflect in, e.g., djangopackages.com that django-organizations has PY3K support.
GauthamGoli/django-organizations,DESHRAJ/django-organizations,bennylope/django-organizations,GauthamGoli/django-organizations,st8st8/django-organizations,DESHRAJ/django-organizations,bennylope/django-organizations,st8st8/django-organizations