Opera fixes and big Opera performance boost.

Add message/state pollling in web-socket-js. Since Opera tends to drop
message events, we can dramatically increase performance by polling
every now for message event data.

Also, add more direct calls to update readyState so that it's not
missed when Opera drops events.

include/vnc.js

@@ -194,9 +194,9 @@ connect: function (host, port, password, encrypt, true_color) {
 disconnect: function () {
     //console.log(">> disconnect");
     if ((RFB.ws) && (RFB.ws.readyState === WebSocket.OPEN)) {
+        RFB.ws.close();
         RFB.updateState('closed');
         RFB.ws.onmessage = function (e) { return; };
-        RFB.ws.close();
     }
     if (Canvas.ctx) {
         Canvas.stop();