title: how to configure saml2 token profile on wso2 carbon sts
body: <p>Is there a way to configure the wso2carbon-sts to work with the saml token profile, instead of the username token profile? </p>
  
  <p>in other words I want to login with the sts by passing a saml2 token, instead of a username and password.</p>
  
  <p>I don't want to use in the ws security header the tag UsernameToken, but something like SecurityTokenReference </p>
  
  <p>I tried modifying some ws policies in the service meta file, and also from the back end gui, but it didn't work. </p>
  
  <p>I'd like to have an hello world for this scenario, does it exists?</p>