update v-if/v-else example to with new rootless syntax

Author: chrisvfritz

src/guide/render-function.md

@@ -214,12 +214,10 @@ Vue.component('anchored-heading', {
 Wherever something can be easily accomplished in plain JavaScript, Vue render functions do not provide a propriety alternative. For example, in a template using `v-if` and `v-for`:
 
 ``` html
-<div>
-  <ul v-if="items.length">
-    <li v-for="item in items">{{ item.name }}</li>
-  </ul>
-  <p v-else>No items found.</p>
-</div>
+<ul v-if="items.length">
+  <li v-for="item in items">{{ item.name }}</li>
+</ul>
+<p v-else>No items found.</p>
 ```
 
 This could be rewritten with JavaScript's `if-else` and `map` in a render function: