manage conflict (generic way) use toast to show error (#588)

* manage conflict (generic way) use toast to show error

* fix httpservice after merge conflict, adapt to use new repository

src/ApplicationCore/Exceptions/DuplicateCatalogItemNameException.cs

@@ -1,14 +0,0 @@
-using System;
-
-namespace Microsoft.eShopWeb.ApplicationCore.Exceptions
-{
-    public class DuplicateCatalogItemNameException : Exception
-    {
-        public DuplicateCatalogItemNameException(string message, int duplicateItemId) : base(message)
-        {
-            DuplicateItemId = duplicateItemId;
-        }
-
-        public int DuplicateItemId { get; }
-    }
-}

src/ApplicationCore/Exceptions/DuplicateException.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace Microsoft.eShopWeb.ApplicationCore.Exceptions
+{
+
+    public class DuplicateException : Exception
+    {
+        public DuplicateException(string message) : base(message)
+        {
+            
+        }
+       
+    }
+}