title: How to customize the text on ion-toggle in ionic2
body: <p>am looking to customize the ion-toggle, to show custom text. I need it to say Yes/No. Tried looking for solutions and found that we can use ion-toggle-text. But that solution does not seem to work in ionic2. Below is the code snippet am using. Tried to use ng-true-value but did not work either.</p>
  
  <pre><code>&lt;ion-toggle ion-toggle-text="Yes;No" ng-true-value="Yes" ng-false-value="No"&gt;
  &lt;/ion-toggle&gt;
  </code></pre>
  
  <p>I could not find anything related to this in ionic documentation for ion-toggle. 
  Can you pls let me know how do I achieve this functionality?</p>