+Property)Set a property on the queue. Supported properties are:
- Change the number of terms that may appear in the message queue before
the next thread_send_message/[2,3]
blocks on it. If the value is higher then the current maximum and the
queue has writers waiting, wakeup the writers. The value can be lower
than the current number of terms in the queue. In that case writers will
block until the queue is drained below the new maximum.