Remove expired ports:
2015-10-01 www/py-django16: End of extended support: April 1, 2015
www/py-django16-tastypie: Uses expired Django version
2017-04-01 www/py-django-pipeline13: Depends on expired www/py-django16, and expired upstream
2017-04-19 www/py-djblets: Does not build with py-django18 see pr: 216758
2017-04-19 security/py-crits: Does not build with py-django18 see pr: 216758
www/py-cactus: Depends on expired Django version
devel/py-django16-tastypie-mongoengine: Uses expired Django version