cleaning up flags.
clarify parser and decoder.
cosmetic change.
layout only
cleaning up.
clarify encoder and builder.
implementing encoder.
payloadLength
frameType
flags
streamId
just cleaning up.
cleaning up.
cleaning up.
cleaning up.
defining Priority.
test for encodeFrame.
Add an unknown frame payload type with the raw data.
Switch fhType in the header to the raw word8 frame type id to retain it for upstream unknown frame handling.
comment.
extending ErrorCode to express unknow frame type.