Use FLEXI-STREAMS:WITH-INPUT-FROM-SEQUENCE and
FLEXI-STREAMS:WITH-OUTPUT-TO-SEQUENCE where appropriate.

Split qmynd into qmynd and qmynd-impl. This is presently a no-op as
neither package exports anything yet, but that will change soon.

New slot parameter :type to override deduced slot type.

Struct now created at the end of parsing with initargs, rather than
being created empty and requring looser types.

Back to stricter struct types.

connections are now possible, not that you can do anything else yet.