title: jhipster 2 : What is the difference between the authentication option?
body: <p>I have updated the jhipster generator from version 1 to version 2. In the previous version we had to choices of authentication when generating a new project. We had the choice between Cookie authentication and Token authentication (with OAuth). This was very clear for me. But in version 2.1.1, we have now three choices :</p>
  
  <pre><code>1 &gt; HTTP Session Authentication (stateful, default Spring Security mechanism)
  2 &gt; OAuth2 Authentication (stateless, with an OAuth2 server implementation)
  3 &gt; Token-based authentication (stateless, with a token)
  </code></pre>
  
  <p>I want to used the authentication both for web and mobile app (ionic-framework), which one to one between 2 and 3 ? Is this choice make my app scalable using clusters ? 
  Thanks</p>