• [BUGFIX] Replace dispatch read/write events assertion with a check.
• [BUGFIX] gQUIC connection close: there is no HEADERS stream without HTTP flag, see issue #220.
• http_client, http_server: add hq protocol support and other flags for use with QUIC Interop Runner.
• Fix: use IP_PMTUDISC_PROBE (not IP_PMTUDISC_DO) on Linux to set Don't-Fragment flag on outgoing packets.
• Fix send_packets_one_by_one on Windows platform when sending multiple iovs, see issue #218.
• Exit echo_client on Windows immediately, see issue #219.