update readme

implementation/16-caching/src/Template/MustacheRenderer.php

@@ -0,0 +1,17 @@
+<?php declare(strict_types=1);
+
+namespace Lubian\NoFramework\Template;
+
+use Mustache_Engine;
+
+final class MustacheRenderer implements Renderer
+{
+    public function __construct(private Mustache_Engine $engine)
+    {
+    }
+
+    public function render(string $template, array $data = []): string
+    {
+        return $this->engine->render($template, $data);
+    }
+}