Align Range v-for HTML sample with actual result (vuejs#904)

Author: Pacoup

src/v2/guide/list.md

@@ -196,7 +196,7 @@ And another for the index:
 
 ``` html
 <div>
-  <span v-for="n in 10">{{ n }}</span>
+  <span v-for="n in 10">{{ n }} </span>
 </div>
 ```