title: how can get index & count in vuejs
body: <p>I have <a href="https://jsfiddle.net/badvz/b12tucho/2/" rel="noreferrer">code like this (JSFiddle)</a></p>
  
  <pre><code>  &lt;li v-for="(itemObjKey, catalog) in catalogs"&gt;this index : {{itemObjKey}}&lt;/li&gt;
  </code></pre>
  
  <p><strong>Output</strong>:<br>
  this index: 0<br>
  this index: 1<br></p>
  
  <p><strong>My question is</strong>:<br></p>
  
  <ol>
  <li>How can I get value index first begin: 1 for example<br> I want
  output like this:<br> this index: 1<br> this index: 2<br><br></li>
  <li>How can I get count from index, i.e. output like this:<br> this index: 1<br> this index: 2<br> this count: 2 field<br></li>
  </ol>