Fix two bugs

- return 2 values instead of pair from READ-RFC822-FIELD
- return alist in correct order from READ-RFC822-HEADERS and
  READ-RFC822-HEADERS-WITH-LINE-BREAKS

scheme/lib/rfc822.scm

@@ -64,9 +64,10 @@
       (lambda (s) (string->symbol (string-map char-upcase s)))))
 
 (define (read-rfc822-field . args)
-  (let ((pair (apply read-rfc822-field-with-line-breaks args)))
-    (cons (car pair)
-	  (string-concatenate (cdr pair)))))
+  (receive (field body)
+      (apply read-rfc822-field-with-line-breaks args)
+    (values field
+	    (string-concatenate body))))
 
 (define (read-rfc822-field-with-line-breaks . args)
   (let-optionals args ((port (current-input-port))
@@ -100,7 +101,7 @@
 	    (read-rfc822-field port read-line)
 	  (if field
 	      (lp (cons (cons field val) alist))
-	      alist))))))
+	      (reverse alist)))))))
 
 (define read-rfc822-headers
   (make-read-rfc822-headers read-rfc822-field))