AGSMPLPUSH-42 "xhr_streaming/xhr_polling protocols are not working"

This PR is dependent upon https://github.com/aerogear/aerogear-simplepush-server/pull/66 which should be processed before this PR.

When testing locally you need to update standalone.xml by either running:
```
wildfly-8.0.0.Final/bin/jboss-cli.sh --file=wildfly-module/src/main/resources/wildfly-config.cli
```
Or manually updating standalone.xml:
```
<server socket-binding="simplepush" password="changeMe!" sockjs-session-timeout="604800000" sockjs-tls="false">
    <datastore>
        <in-memory/>
    </datastore>
</server>
```
A very basic client is available:
https://github.com/danbev/aerogear-simplepush-server/blob/AGSMPLPUSH-42-polling-transports-fix/server-netty/src/test/resources/sockjs-client.html
This has to be run in a web server and allows you to change the SockJS transport protocols.