add start end time for min max

Author: abuzuhri

Source/FikaAmazonAPI/ConstructFeed/JsonMessages/PriceData.cs

@@ -9,5 +9,7 @@ public class PriceData
     public class SchedulePriceData
     {
         public decimal value_with_tax { get; set; }
+        public string start_at { get; set; }
+        public string end_at { get; set; }
     }
 }