Client not receiving responses from server after nginx proxy.
Hey,

So I've been fiddling around with Ratchet trying to get a wss connection working with the SSL handled by a Nginx server, the original implementation over unencrypted connections worked fine, but after using the encryption and a proxy from nginx the server receives the connection but the client appears to hang waiting for the handshake to complete which ultimately fails. I have a feeling that the server is maybe not sending the data to the client because of the proxy, this is my nginx configuration:

```
server {
        listen 443;

        root html;
        index index.html index.html;

        ssl on;
        ssl_certificate /etc/nginx/ssl/websocket.crt;
        ssl_certificate_key /etc/nginx/ssl/websocket.key;
        ssl_session_cache shared:SSL:10m;
        ssl_session_timeout 5m;

        access_log /var/log/wss-access-ssl.log;
        error_log /var/log/wss-error-ssl.log info;

        location / {
                access_log off;
                proxy_pass http://localhost:40000;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header Host $host;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

                # WebSocket support (nginx 1.4)
                proxy_http_version 1.1;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection "upgrade";
                proxy_set_header X-Forwarded-Proto https;
                proxy_read_timeout 86400; # neccessary to avoid websocket timeout disconnect
                proxy_redirect off;
        }
}
```
