Fix url tag for django 1.4
Fix url tag for django 1.4

kcsry/django-filebrowser-no-grappelli,kcsry/django-filebrowser-no-grappelli,kcsry/django-filebrowser-no-grappelli,djkartsa/django-filebrowser-no-grappelli,djkartsa/django-filebrowser-no-grappelli,djkartsa/django-filebrowser-no-grappelli