title: FOSUserBundle not applying User entity changes
body: <p>I have just installed FosUserBundle in a Symfony version 2.3.3 application.
  I'm able to manage users, login, register and whatnot but changes I make to my User class in MyApp\UserBundle\Entity aren't being applied when I run app/console doctrine:schema:update</p>
  
  <p>The database structure contains:
  id,
  username,
  username_canonical,
  email,
  email_canonical,
  enabled,
  salt,
  password,
  last_login,
  locked,
  expired,
  expires_at,
  confirmation_token,
  password_requested_at,
  roles,
  credentials_expired,
  credentials_expire_at</p>
  
  <p>The field that I have added, rate, isnt being created in the database structure no matter what I do.</p>
  
  <p>Inside /app/AppKernel.php</p>
  
  <pre><code>        new MyApp\UserBundle\MyAppUserBundle(),
          new FOS\UserBundle\FOSUserBundle(),
  </code></pre>
  
  <p>Inside /app/config/config.yml</p>
  
  <pre><code>fos_user:
      db_driver: orm
      firewall_name: main
      user_class: MyApp\UserBundle\Entity\User
      registration:
          confirmation:
              enabled:    true
  </code></pre>
  
  <p>And inside /src/MyApp/UserBundle/Entity/User.php</p>
  
  <pre><code>&lt;?php
  
  namespace MyApp\UserBundle\Entity;
  
  use FOS\UserBundle\Model\User as BaseUser;
  use Doctrine\ORM\Mapping as ORM;
  
  /**
   * User
   *
   * @ORM\Table(name="fos_user")
   * @ORM\Entity(repositoryClass="MyApp\UserBundle\Entity\UserRepository")
   */
  class User extends BaseUser
  {
      /**
       * @var integer
       *
       * @ORM\Column(name="id", type="integer")
       * @ORM\Id
       * @ORM\GeneratedValue(strategy="AUTO")
       */
      protected $id;
  
      /**
       * @var string
       *
       * @ORM\Column(name="token", type="string", length=255)
       */
      private $token;
  
      /**
       * @var integer
       *
       * @ORM\Column(name="rate", type="integer")
       */
      private $rate;
  
  
      /**
       * Get id
       *
       * @return integer 
       */
      public function getId()
      {
          return $this-&gt;id;
      }
  
      /**
       * Set token
       *
       * @param string $token
       * @return User
       */
      public function setToken($token)
      {
          $this-&gt;token = $token;
  
          return $this;
      }
  
      /**
       * Get token
       *
       * @return string 
       */
      public function getToken()
      {
          return $this-&gt;token;
      }
  
      /**
       * Set rate
       *
       * @param integer $rate
       * @return User
       */
      public function setRate($rate)
      {
          $this-&gt;rate = $rate;
  
          return $this;
      }
  
      /**
       * Get rate
       *
       * @return integer 
       */
      public function getRate()
      {
          return $this-&gt;rate;
      }
  }
  </code></pre>