Implementation of "Async Support" for WebSocket transport and Long-Polling fallback to use on JBoss EAP 6.2 with JBoss Native Connector

Implementation of "Async Support" for WebSocket transport and Long-Polling fallback to use on JBoss EAP 6.2 with JBoss Native Connector.

This is a approach to solve fix issue https://github.com/Atmosphere/atmosphere/issues/1670.

It's necessary configuring "init-param" for "AtmosphereServlet" in the web.xml for use this async support:

`<init-param>`
&nbsp;&nbsp;&nbsp;&nbsp;`<param-name>org.atmosphere.cpr.asyncSupport</param-name>`
&nbsp;&nbsp;&nbsp;&nbsp;`<param-value>org.atmosphere.container.JBossAsyncSupportWithWebSocket</param-value>`
`</init-param>`