title: Cordova Plugin Push error : PushNotification is not defined
body: <p>I followed all the instructions to install the PhoneGap Push Plugin at : </p>
  
  <p><a href="https://github.com/phonegap/phonegap-plugin-push/blob/master/docs/INSTALLATION.md" rel="nofollow noreferrer">https://github.com/phonegap/phonegap-plugin-push/blob/master/docs/INSTALLATION.md</a></p>
  
  <p>I have also read the example code found here : </p>
  
  <p><a href="https://github.com/phonegap/phonegap-plugin-push/blob/master/docs/EXAMPLES.md" rel="nofollow noreferrer">https://github.com/phonegap/phonegap-plugin-push/blob/master/docs/EXAMPLES.md</a></p>
  
  <p>And I tried the plugin with the following sample code :</p>
  
  <pre><code>document.addEventListener("deviceready", notifications(), false);
  
  //NOTIFICATIONS
  function notifications(){
      try{
          var push = PushNotification.init({
            android: {}
          });
      }
      catch(err){
          alert("error : " + err);
      }
  }
  </code></pre>
  
  <p>I builded the APK file and I installed it on a real device. When the app is starting, I get the following alert : <strong>error : ReferenceError: PushNotification is not defined</strong></p>
  
  <p>I'm working with : Cordova CLI 8.0.0, Cordova Android 7.0.0, PhoneGap Push Plugin 2.1.2</p>