I went with one direction, which I think works best as it has a direct relation to the path identifier. MAX_STREAMS uses a count because of the way in which streams are allocated odd/even. That awkwardness we have for streams isn't necessary here.
This part is merged into the current branch to make the modification of transport parameter and frame have the same semantics and easier to review.
This is the original proposal of Martin's PR:
This part is merged into the current branch to make the modification of transport parameter and frame have the same semantics and easier to review.