[1.6.x] Improved get_media_prefix template tag example.
[1.6.x] Improved get_media_prefix template tag example.

Backport of 9a4a9a8a49ed3e38f3038b8d6fc7c405256271f1 from master

redhat-openstack/django,redhat-openstack/django,felixjimenez/django,redhat-openstack/django,felixjimenez/django,felixjimenez/django,django-nonrel/django,django-nonrel/django,django-nonrel/django,redhat-openstack/django,django-nonrel/django,felixjimenez/django