Added DeprecationWarning to ``custom_admin_media_prefix`` tag.
Added DeprecationWarning to ``custom_admin_media_prefix`` tag.

wardi/django-filebrowser-no-grappelli,wardi/django-filebrowser-no-grappelli,wardi/django-filebrowser-no-grappelli,wardi/django-filebrowser-no-grappelli