更改app支付 package签名

go/gopath/src/fohow.com/libs/wx_mp/pay.go

@@ -162,8 +162,9 @@ func GetAppPayData(outTradeNo string, totalPrice int64, body, notifyUrl, remoteI
 	ret = map[string]string{
 		"appId":     appId,
 		"partnerId": outTradeNo,
-		"timeStamp": fmt.Sprintf("%d", time.Now().Unix()),
 		"prepayId":  prepayId,
+		"mch_id":    mechantInfo.MchId,
+		"timeStamp": fmt.Sprintf("%d", time.Now().Unix()),
 		"signType":  "MD5",
 		"nonceStr":  nonce_str}
 	ret["paySign"] = mch.Sign(ret, mechantInfo.ApiKey, nil)