Bug Fixes server: add upgrading process to poll_without_shutdown() (#1530) (c6e90b7b) Features client: implement Clone for Destination (15188b7c) server: add http1_writev config option for servers (810435f1, closes #1527) add http1_only configuration (14d9246d, closes #1512) add try_into_parts() to conn::Connection (#1531) (c615a324)