title: open InAppBrowser on ionicModal
body: <p>I want open a web page in my app, I know I should use ngCordova <code>InAppBrowser</code> plugin, but how can I open the webpage in <code>$ionicModal</code> ? like twitter, facebook mobile apps and ...</p>
  
  <p>I have this button :</p>
  
  <pre><code>&lt;button class="button button-block button-assertive" ng-click="doPay()"&gt;Pay&lt;/button&gt;
  </code></pre>
  
  <p>and in <code>doPay()</code> I have :</p>
  
  <pre><code>$scope.doPay = function(){
      window.open(url, '_system', 'location=no');
  };
  </code></pre>
  
  <p>but this code use external app (<code>Safari</code>), I want open in my application.</p>