Added Public to StandardLayouts.

framework/src/Volo.Abp.AspNetCore.Mvc.UI/Volo/Abp/AspNetCore/Mvc/UI/Theming/StandardLayouts.cs

@@ -4,6 +4,7 @@
     {
         public const string Application = "Application";
         public const string Account = "Account";
+        public const string Public = "Public";
         public const string Empty = "Empty";
     }
 }