title: Has no exported member 'InjectionToken'
body: <p>I am building an Angular2 app with firebase. The problem is that the entire application is working fine in Visual Studio Code but not in c9, even though my procedure of installing all the packages is the same. In c9 I am getting the error : </p>
  
  <blockquote>
    <p>ERROR in
    /home/ubuntu/workspace/map-report/node_modules/angularfire2/app/firebase.app.module.d.ts
    (1,10): Module
    '"/home/ubuntu/workspace/map-report/node_modules/@angular/core/index"'
    has no exported member 'InjectionToken'.</p>
    
    <p>ERROR in
    /home/ubuntu/workspace/map-report/node_modules/angularfire2/angularfire2.d.ts
    (3,10): Module
    '"/home/ubuntu/workspace/map-report/node_modules/@angular/core/index"'
    has no exported member 'InjectionToken'.</p>
  </blockquote>
  
  <p>I have copy-pasted all the code from my functional code in VS Code to c9, but even then I am getting this error. Can't understand what is the problem. </p>
  
  <p>Any help would be greatly appreciated. Thanks. </p>