Fixed GetStackSize exception when items are missing.

Fix for some items (construction, coal etc) not stacking correctly.

Author: AnExiledDev

StackSizeController.cs

@@ -291,14 +291,19 @@ private void OnEntitySpawned(MiniCopter heli)
                     return;
 
                 var hookResult = Interface.CallHook("OnVendorHeliFuelAdjust", heli);
-                if (hookResult is bool && (bool) hookResult == false)
+                if (hookResult is bool && (bool)hookResult == false)
                     return;
 
                 fuelItem.amount = 100;
                 fuelItem.MarkDirty();
             });
         }
 
+        int OnMaxStackable(Item item)
+        {
+            return GetStackSize(item.info);
+        }
+
         #endregion
 
         #region Commands