emul: make verbose staging the default

I always keep it on myself. I can imagine it's especially useful to
newcomers.

emul/stage.c

@@ -42,8 +42,8 @@ static uint8_t iord_stdio()
 
 static void iowr_stdio(uint8_t val)
 {
-    // uncomment when you need to debug staging
-    // putc(val, stderr);
+    // comment if you don't like verbose staging output 
+    putc(val, stderr);
 }
 
 static void iowr_here(uint8_t val)