Add IsNeutralDrop bool to Dota 2 Game Item

Author: Justin

src/Steam.Models/DOTA2/ItemAbilitySchemaItemModel.cs

@@ -9,7 +9,7 @@ public class ItemAbilitySchemaItemModel
         public string Name { get; set; }
 
         /// <summary>
-        /// Valve's source files don't include localized names. Instead, the callers are responsibel for populating this value
+        /// Valve's source files don't include localized names. Instead, the callers are responsible for populating this value
         /// by performing a lookup in the various language/token mapping files.
         /// </summary>
         public string LocalizedName { get; set; }
@@ -87,5 +87,7 @@ public class ItemAbilitySchemaItemModel
         public bool? ItemContributesToNetWorthWhenDropped { get; set; }
 
         public string ItemDisassembleRule { get; set; }
+
+        public bool? ItemIsNeutralDrop { get; set; }
     }
 }