发起和结束咨询的消息由系统发出，发送者ID记录操作人！

src/server/models/sessions/topics.js

@@ -230,7 +230,7 @@ class Topics extends RedisModel {
            msg.sender_id = messages.sender_id;
            msg.sender_name = messages.sender_name;
            msg.content_type = 6;
            msg.content = messages.description;
            msg.content = "咨询问题:"+messages.description;
            msg.timestamp = new Date(new Date().getTime());
            sessions.saveMessageByTopic(msg, sessionId, function (err, msgId) {
                if (messages.img) {