public ActionResult Preview()
 {
     var model = new ProductModel() {ProductCategories = new Dictionary<string, string>()};
     var vm = new ViewModel(UIKeysProductDrafts.Preview.ProductCategorySelect, p => p.Html.Action("Preview", new { model }));
     return ViewModel(vm);
 }
 public ActionResult Edit()
 {
     var model = new ProductModel() { ProductCategories = _productCategoriesDict };
     var vm = new ViewModel(UIKeysProductDrafts.Edit.ProductCategorySelect, p => p.Html.Action("Edit", new { model }));
     return ViewModel(vm);
 }