WebSocketCommandReverseServer: correctly process messages that are received while we are waiting for a message handler to finish the reply
WebSocketCommandReverseServer: correctly process messages that are received while we are waiting for a message handler to finish the reply

Even if we call conn->pause_reading(), WebSocket++ may already have received further messages
in its buffer, which it will still pass to us. We get around this problem by buffering
these messages in our own buffer.

phusion/passenger,phusion/passenger,phusion/passenger,phusion/passenger,phusion/passenger,phusion/passenger,phusion/passenger,phusion/passenger