我想使用AFNetworking2.0获取此站点中RSS的XML数据:http://www.ifanr.com/feed但我明白了:Error:ErrorDomain=AFNetworkingErrorDomainCode=-1016"Requestfailed:unacceptablecontent-type:application/rss+xml"UserInfo=0x8c21d50{NSErrorFailingURLKey=http://www.ifanr.com/feed,AFNetworkingOperationFailingURLResponseErrorKey={URL: