Lockdown mode for old catalog

WPFCatalog/Controls/GeneralSettingsControl.xaml

@@ -7,10 +7,15 @@
         xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"
         xmlns:Controls="clr-namespace:MahApps.Metro.Controls;assembly=MahApps.Metro"
         xmlns:iconPacks="http://metro.mahapps.com/winfx/xaml/iconpacks"
+        xmlns:System="clr-namespace:System;assembly=mscorlib"
+        xmlns:catalogLib="clr-namespace:CatalogLib;assembly=CatalogLib"
         mc:Ignorable="d" 
              d:DesignHeight="900" d:DesignWidth="500"
              d:DataContext="{d:DesignInstance wpfCatalog:MainWindowViewModel}"
              >
+    <UserControl.Resources>
+        
+    </UserControl.Resources>
     <Grid>
         <ScrollViewer>
             <StackPanel Orientation="Vertical">