title: ionic 2 themeablebrowser icons are not displaying
body: <p>I am trying to open links using themeable browser plugin. I managed to make it work but I couldn't get the icons displayed? I tried changing hex values but it didn't help. Below is my code,</p>
  
  <pre><code>navigate() {
  let options = {
   statusbar: {
       color: '#ffffff'
   },
   toolbar: {
       height: 44,
       color: '#2e6abf'
   },
   title: {
       color: '#ffffff',
       showPageTitle: true
   },
   backButton: {
       image: 'back',
       imagePressed: 'back_pressed',
       align: 'left',
       event: 'backPressed'
   },
   forwardButton: {
       image: 'forward',
       imagePressed: 'forward_pressed',
       align: 'left',
       event: 'forwardPressed'
   },
   closeButton: {
       image: 'close',
       imagePressed: 'close_pressed',
       align: 'left',
       event: 'closePressed'
   },
   customButtons: [
       {
           image: 'share',
           imagePressed: 'share_pressed',
           align: 'right',
           event: 'sharePressed'
       }
   ],
   menu: {
       image: 'menu',
       imagePressed: 'menu_pressed',
       title: 'Test',
       cancel: 'Cancel',
       align: 'right',
       items: [
           {
               event: 'helloPressed',
               label: 'Hello World!'
           },
           {
               event: 'testPressed',
               label: 'Test!'
           }
       ]
   },
   backButtonCanClose: true
  };
  
  let browser = new ThemeableBrowser('http://sparklms.com', '_blank', options);
  
    }
  </code></pre>
  
  <p>Any help would be much appreciated. </p>
  
  <p>Thanks</p>