Changed accumulator test/bind order to bind/test

This means vectoring exits directly when the index loop variable =
:length.

It also means :final has to change.

goof/iterators.scm

@@ -512,13 +512,13 @@
 ;; this is an internal "accumulator". It is used for final tests
 ;; :final in goof differs from in racket. It is lexical, meaning it
 ;; is tested where it is placed in the clauses, and any subloop is
-;; executed completely.
+;; executed until exhaustion.
 (define-syntax final
   (syntax-rules (:acc)
     ((_ :acc ((var) (test)) n . rest)
      (n ()
-        ((final #f test))
-        (final)
+        ((var #f test))
+        ()
         ()
         ()
         . rest))))