- [API] Drop support for Q039.
- Improve ACK-queuing logic. Send an ACK once in a while if
peer keeps on sending non-ack-eliciting packets.
- Improve Alt-Svc string: Q050 and later are not included in
the old-style "quic" string.
- Send stateless resets if connection could not be promoted.
- Schedule MAX_DATA if needed when DATA_BLOCKED is received.
- Use ls-qpack 0.11.2 -- needed for server push optimization.
- Code cleanup: handle some error cases, improve logging.
- [BUGFIX] Initial packet size check for IETF mini conn applies to
UDP payload, not QUIC packet.
- Support old and new school loss_bits transport parameter.
- Use Q run length of 64 as suggested in the loss bits Draft.
- Undo square wave count when packet is delayed.
- Code cleanup; minor fixes.
