Messages Missing in Pusher Example
Thank you very much for your wonderful library. 

I have integrated pusher (Push to an Existing Site) example and successfully received the messages over websocket. But all the messages sent are not received. Scenario is described below. Please help me to figure out the issue.

Opened 2 browser windows
One for Blog Submission and other for Blog Listing

Bolg 1 Submitted
Blog 1 Listed via websocket

Blog 2 Submitted
Blog 2 not listed.

Blog 3 Submitted
Blog 3 Listed via websocket.

Blog 4 Submitted
Blog 4 not Listed.

After Blog Submission
```php
 $entryData = array(
    'category' => 'kittensCategory'
     , 'title' => $this->blog->text
     , 'article' => $this->blog->text
     , 'when' => time()
     , 'count' => $cnt
 );

$context = new \ZMQContext();
$socket = $context->getSocket(\ZMQ::SOCKET_PUSH, 'my pusher');
$socket->connect("tcp://10.2.2.108:5555");
$socket->send(json_encode($entryData));
```
push-server.php

```php
<?php
    require dirname(__DIR__) . '/vendor/autoload.php';

    $loop   = React\EventLoop\Factory::create();
    $pusher = new App\Pusher;

    // Listen for the web server to make a ZeroMQ push after an ajax request
    $context = new React\ZMQ\Context($loop);
    $pull = $context->getSocket(ZMQ::SOCKET_PULL);
    $pull->bind('tcp://127.0.0.1:5555'); // Binding to 127.0.0.1 means the only client that can connect is itself
    $pull->on('message', array($pusher, 'onBlogEntry'));

    // Set up our WebSocket server for clients wanting real-time updates
    $webSock = new React\Socket\Server('0.0.0.0:8080', $loop); // Binding to 0.0.0.0 means remotes can connect
    $webServer = new Ratchet\Server\IoServer(
        new Ratchet\Http\HttpServer(
            new Ratchet\WebSocket\WsServer(
                new Ratchet\Wamp\WampServer(
                    $pusher
                )
            )
        ),
        $webSock
    );
$loop->run();

```
Pusher.php
```php
<?php

namespace App;

use Ratchet\ConnectionInterface;
use Ratchet\Wamp\WampServerInterface;

class Pusher implements WampServerInterface {

    /**
     * A lookup of all the topics clients have subscribed to
     */
    protected $subscribedTopics = array();

    public function onSubscribe(ConnectionInterface $conn, $topic) {
         
        $this->subscribedTopics[$topic->getId()] = $topic;
    }
    public function onUnSubscribe(ConnectionInterface $conn, $topic) {
        
    }
    public function onOpen(ConnectionInterface $conn) {
        
       
    }
    public function onClose(ConnectionInterface $conn) {
        
       
    }
    public function onCall(ConnectionInterface $conn, $id, $topic, array $params) {
        // In this application if clients send data it's because the user hacked around in console
        $conn->callError($id, $topic, 'You are not allowed to make calls')->close();
    }
    public function onPublish(ConnectionInterface $conn, $topic, $event, array $exclude, array $eligible) {
         
        // In this application if clients send data it's because the user hacked around in console
        $conn->close();
    }
    public function onError(ConnectionInterface $conn, \Exception $e) {
        
    }
    /**
     * @param string JSON'ified string we'll receive from ZeroMQ
     */
    public function onBlogEntry($entry) {
	
        $entryData = json_decode($entry, true);

        // If the lookup topic object isn't set there is no one to publish to
        if (!array_key_exists($entryData['category'], $this->subscribedTopics)) {
            return;
        }

        $topic = $this->subscribedTopics[$entryData['category']];

        // re-send the data to all the clients subscribed to that category
        $topic->broadcast($entryData);
    }

    /* The rest of our methods were as they were, omitted from docs to save space */
}
```
Hint: When I debugged, in the function onBlogEntry it enters into 
```php
 if (!array_key_exists($entryData['category'], $this->subscribedTopics)) {
    return;
}
```


 