* contrib/sly-mrepl.el: Fix top doc.
(sly-mrepl): Don't list license and authord in contrib def.
(sly-mrepl--prompt): `accept-process-output' here.
(:write-values): Not here.
(:evaluation-aborted): Print condition.

* contrib/swank-mrepl.lisp (listener-channel): Remove DEDICATED slot, add
IN and OUT.
(initialize-instance): Make IN and OUT here, possibly blocking
while waiting for Emacs to connect to OUT.
(create-mrepl): Don't open DEDICATED here.
(mrepl-eval): Use HANDLER-CASE to catch errors. Always flush
streams.
(flush-streams): New function.
(send-prompt): Just send prompt.