MINOR: tevt/mux-h1: Report termination events for the H1C and H1S

MINOR: tevt/mux-h1: Report termination events for the H1C and H1S

shutdown for reads (read0), receive errors, shutdown for writes and timeouts
are reported. It is not too hard to know where to report events generated by
HAProxy (timeouts and shutw). For detected events (shutr and receive error),
it is not so simple. These events must not be reported when they are
detected but when the mux can handle them. For instance, some unprocessed
input data may block a read0. So, the experience will tell us if these
events are reported at the rigth time and on the right conditions.

For now, no internal errors (parsing errors, protocol errors, intenral
errors...) are reported because these event types have not yet been added.