If describing the status of a pipeline, write all elements of the pipeline
and show the status of the last process (which would also end up in $?).
Only write one report per job, not one for every process that exits.
To keep some earlier behaviour, if any process started by the shell in a
foreground job terminates because of a signal, write a message about the
signal (at most one message per job, however).
Also, do not write messages about signals in the wait builtin in
non-interactive shells. Only true foreground jobs now write such messages
(for example, "Terminated").