v0.3.1: Consistency in identity.isAuthenticated

The isAuthenticated method of the UserIdentity type has been adjusted to provide a consistent API with other custom Identity objects. All isAuthenticated methods on Identity objects now have this signature:

isAuthenticated(function(err, cb){

});

This allows you to check authentication in your activities, like this:

  // this now works for the UserIdentity, as well as custom identities
activities.can("do.something", function(identity, params, cb){

  // validate authentication first
  identity.isAuthenticated(function(err, isAuth){
    if (err) { return cb(err); }
    cb(null, isAuth);
  });

  // now write other code to check authorization

});