two minor changes to make prototyping in the racket REPL nicer

gem300.rkt

@@ -16,7 +16,9 @@
     (read-response c-in))
 
   (println status)
-  (println header))
+  (println header)
+
+  c-in)
 
 (define (read-response (c-in (current-input-port)))
   (define maxlen 1027)
@@ -91,5 +93,3 @@
   (display "G300> ")
   (dispatch-command (read-line))
   (repl))
-
-(repl)