title: How to make text field non editable
body: <p>I have text field, which uses datepicker. I want text field should be non-editable so we can edit only using datepicker. </p>
  
  <pre><code>kindly have a look on 
  http://plnkr.co/edit/zekPQhWK6SgWdK2phRnJ?p=preview
  </code></pre>
  
  <p>Any help appreciated.</p>