* srfi-1.scm (iota map for-each map-in-order list-index member

* srfi-1.scm (iota map for-each map-in-order list-index member
delete delete! assoc): Marked as replacements.

* goops.scm (define-extended-generics): New syntax.
(<class> <operator-class> <entity-class> <entity>): Marked as
replacements.

* boot-9.scm (module-override!, make-mutable-parameter,
lookup-duplicates-handlers, default-module-duplicates-handler):
New functions.
(process-duplicates): Don't call duplicates handlers for duplicate
bindings of the same variable.
(process-define-module): Process #:replace.
(compile-interface-spec, resolve-interface): Process #:prefix.

* format.scm (format): Marked as replacement.

* threads.scm (future, future-ref): Marked as replacements.