减少通信字段；通信添加比赛字段；

Model/MsgModel.cs

@@ -1,4 +1,5 @@
-using System;
+using Newtonsoft.Json;
+using System;
 using System.Collections.Generic;
 using System.Text;
 
@@ -39,6 +40,6 @@ namespace OnlineUserPool.Model
         /// </summary>
         public double WeightKg { get; set; }
 
-        
+        public int Competitionid { get; set; }
     }
 }