title: json login on spring security
body: <p>I'm building a REST back end based on spring and i'm using spring security to secure the requests. But i'm lookin for an issue to login by sending parameters in json rather than defaults parameters sent by the default login page of spring security.</p>
  
  <p>I'm working with spring security 4.0.1 and spring 4.1</p>
  
  <p>Any issue please?</p>