rgw: swift: The http referer should be parsed to compare in swift API

rgw: swift: The http referer should be parsed to compare in swift API
The http referer should be parsed to compare with the url set on the container read acl. If we set .r:www.example.com on container read acl, we should parse the hostname 'www.example.com' of the http referer like 'http://www.example.com' from the http request.

Fixes: http://tracker.ceph.com/issues/18685
Signed-off-by: Jing Wenjun <jingwenjun@cmss.chinamobile.com>