Hot Rod server not dealing with pipe requests properly

This might not become so apparent with the current synchronous Java client, but with fully asynchronous clients such as the Javascript one, multiple requests can be piped one after the other.

Hot Rod server does not often deal with those well, showing exceptions such as:

org.infinispan.server.hotrod.InvalidMagicIdException: 
Error reading magic byte or message id: 119

org.infinispan.server.hotrod.UnknownVersionException: 
Unknown version:-96

This exceptions appear when applying considerable load with the Javascript client (see HRJS-24), but the same effect can be replicated with a Netty based, fully asynchronous client, such as the simplified version used here.