Add py-django-ranged-response 0.2.0

This is a modified FileResponse that returns 'Content-Range' headers with the
HTTP response, so browsers (e.g. Safari 9+) that request the file, can stream
the response properly.

WWW: https://github.com/i3thuan5/django-ranged-response

PR: 228132
Submitted by: Kai <freebsd_ports@k-worx.org>