总的orderbook使用20个，日志调整

api_kucoin.js

@@ -348,7 +348,7 @@ class biboxApi {
     this._request("POST","/v1/orderpending","orderpending/pendingHistoryList",params,callback);
   }
   getOrderbook(symbol,depth,bindIP,callback){
-    this._publicRequest("/v1/open/orders",{"symbol":symbol},callback,bindIP);
+    this._publicRequest("/v1/open/orders",{"symbol":symbol,"limit":20},callback,bindIP);
   }
 }