title: supertest: test the redirection url
body: <p>with supertest, I can test the redirection code 302</p>
  
  <pre><code>var request = require('supertest');
  var app = require('../server').app;
  
  describe('test route', function(){
    it('return 302', function(done){
      request(app)
        .get('/fail_id')
        .expect(302, done);
    });
    it('redirect to /');
  });
  </code></pre>
  
  <p>how I can test the url objetive to redirect ? </p>