title: How to add multiple data attributes in ionic 3 select option
body: <p>I'm trying to add attributes in select option,
  I have json like-</p>
  
  <pre><code>this.userlists = { "id":1 "name":"John", "age":31 };
  
  &lt;ion-select [(ngModel)]="userdtl"&gt;
      &lt;ion-option *ngFor="let ul of userlists" value="{{ul.id}}"&gt;{{ul.name}}&lt;/ion-option&gt;
  &lt;/ion-select&gt;
  </code></pre>
  
  <p>How to add "<strong>age</strong>" attributes in option, because i have need user id and age also when submit form</p>