Half-closed reads removes the possibility to communicate Stream closure

[lukaspj]

#131 breaks a very fundamental thing in Yamux, the ability to inform the other end of the line that we are not interested in the Stream anymore.
This forces us to roll-back to a previous version.

This could be solved by #115 I believe, if we had a "remote closed" channel we could listen on to detect the half-closed state.

[lukaspj]

Never mind I crossed some wires here, will close