Allow substitution of Infinispan server properties

From Brian S:

"Can whatever reads these properties (HotRodServer and MemcachedServer or some delegate) do system property substitution? Then the file has
infinispan.server.port = ${jboss.infinispan.server.port:11311}

or, if the substitution logic is simpler, even just

infinispan.server.port = ${jboss.infinispan.server.port}

and we tweak the config in datagrid/conf/bindingservice/beans to set jboss.infinispan.server.port"