HotRod-based distributed session manager

WildFly is currently able to externalize web sessions to a remote Infinispan-server cluster by use of an invalidation cache and a hotrod-store. This however requires clustering on the WF side, and is generally less efficient than a session manager that uses hotrod directly.
We have, in fact, already implemented this for Tomcat (http://github.com/wildfly-clustering/wildfly-clustering-web-tomcat) designed such that the core implementation can be shared with WildFly. This jira represents the completion of this work, and encompasses:

• Porting the wildfly-clustering-web-hotrod module to WildFly.
• Enhancing the distributable-web subsystem to allow configuration of this new session manager implementation
• Enhancing deployment descriptor support to allow deployment-specific session management using the new session manager implementation