Bug 41 implementation in bfe5b292 omitted adding the command to the Explorer interface

https://winscp.net/tracker/41

Source commit: 2672e1d1797c14960a64f37803b24b9981619a7d

source/forms/ScpExplorer.dfm

@@ -71,6 +71,9 @@ inherited ScpExplorerForm: TScpExplorerForm
         object TBXItem41: TTBXItem
           Action = NonVisualDataModule.RemotePropertiesAction2
         end
+        object TBXItem61: TTBXItem
+          Action = NonVisualDataModule.CalculateDirectorySizesAction
+        end
         object TBXSeparatorItem8: TTBXSeparatorItem
         end
         object TBXItem30: TTBXSubmenuItem

source/forms/ScpExplorer.h

@@ -327,6 +327,7 @@ __published:
   TTBXSubmenuItem *TBXSubmenuItem10;
   TTBXItem *TBXItem168;
   TTBXSeparatorItem *TBXSeparatorItem23;
+  TTBXItem *TBXItem61;
   void __fastcall RemoteDirViewUpdateStatusBar(TObject *Sender,
           const TStatusFileInfo &FileInfo);
   void __fastcall UnixPathComboBoxBeginEdit(TTBEditItem *Sender,