Making requestListener for the construction of a http.Server optional, as it is for net.Server

lib/http.js

@@ -521,7 +521,11 @@ function flushMessageQueue (socket, queue) {
 
 function Server (requestListener) {
   net.Server.call(this);
+  
+  if(requestListener){
     this.addListener("request", requestListener);
+  }
+  
   this.addListener("connection", connectionListener);
 }
 sys.inherits(Server, net.Server);