Added a separator for fitlers on component

inabox.wpf/DynamicGrid/DynamicGridFilterButtonComponent.cs

@@ -137,6 +137,8 @@ public class DynamicGridFilterButtonComponent<T>
         var multipleFilters = menu.AddCheckItem("Use Multiple Filters", MultipleFilters_Click, MultipleFilters);
         multipleFilters.StaysOpenOnClick = true;
 
+        menu.AddSeparatorIfNeeded();
+
         var filters = Configuration.Load();
         foreach (var filter in filters)
         {
@@ -150,7 +152,7 @@ public class DynamicGridFilterButtonComponent<T>
 
         if (Security.IsAllowed<CanCustomiseFilters>())
         {
-            menu.AddSeparator();
+            menu.AddSeparatorIfNeeded();
             menu.AddItem("Manage Filters", null, () =>
             {
                 var window = new DynamicGridFilterEditor(filters, typeof(T));