* Common race condition is fixed by identifying that Client.respHandler
  can be completely removed since all respHandler operations (get, put
  and invocation) can be moved into the Client.processLoop goroutine,
  meaning that zero locking is required. This race condition resulted
  in a deadlock that was resolved by the response timeout at the
  end of client.Do, returning ErrLostConn

* Rare race condition is fixed by changing responseHandlerMap.get
  to .getAndRemove. This race condition resulted in the innerHandler
  for a new dtJobCreated assigned in client.Do overriding a stale older
  dtJobCreated request, and the newer innerHandler being removed by an
  older dtJobCreated in client.processLoop > client.handleInner. When
  the newer dtJobCreated response was received, the handler for it had
  already been deleted. This was resolved by the response timeout at the
  end of client.Do, returning ErrLostConn