public static ModelNode AddReusableHTMLItem(this ModelNode model, ReusableHTMLItemDefinition definition, Action<ModelNode> action)
 {
     return model.AddDefinitionNode(definition, action);
 }
 public static ModelNode AddReusableHTMLItem(this ModelNode model, ReusableHTMLItemDefinition definition)
 {
     return AddReusableHTMLItem(model, definition, null);
 }