Implement the new render functions.

src/bin.rs

@@ -44,10 +44,11 @@ fn main() {
         .first()
         .expect("There should be more than 1 template")
         .name;
+    let breadcrumbs = vec![&context as &dyn ContextElement];
     println!(
         "{}",
         dust_renderer
-            .render(main_template_name, &context)
+            .new_render(main_template_name, &breadcrumbs)
             .expect("Failed to render")
     );
 }