Major Description
Currently the Java Broker uses the AMQP 0-10 transport classes defined in the common project.
These classes implement a blocking wait when a close is called on a session, waiting for the peer to confirm the close.
The broker should never block, moreover, because the broker is blocking it will possibly never see the close confirmation as it will need to first read past other commands sent by the client prior to it receiving the broker initiated close.
To fix this we need to remove the blocking from the broker, and to also implement the ignoring of incoming commands when the session is in a "closing" state.