title: does not contain any mapped entities while generating getter and setter
body: <p>i am tying to create <code>one to one</code> relation in symfony 2 using <code>doctrine</code> </p>
  
  <p>here is my entity class</p>
  
  <pre><code>&lt;?php
  
  namespace Travel\HomeBundle\Entity;
  
  use FOS\UserBundle\Entity\User as BaseUser;
  use Doctrine\ORM\Mapping as ORM;
  
  /**
   * @ORM\Entity
   * @ORM\Table(name="fos_user")
   */
  class User extends BaseUser
  {
      /**
       * @ORM\Id
       * @ORM\Column(type="integer")
       * @ORM\GeneratedValue(strategy="AUTO")
       */
      protected $id;
  
      /** @ORM\Column(name="facebook_id", type="string", length=255, nullable=true) */
      protected $facebook_id;
  
      /** @ORM\Column(name="facebook_access_token", type="string", length=255, nullable=true) */
      protected $facebook_access_token;
  
  
  
       /** 
  
       @ORM\Column(name="travel_id", type="string", length=255, nullable=true)
       @ORM\OneToOne(targetEntity="Travel\HomeBundle\Entity\Client") 
       @ORM\JoinColumn(name="travel_id", referencedColumnName="id") 
  
       */
  
      protected $travel_id;
  
  
      /** 
  
        @ORM\Column(name="travel_access_token", type="string", length=255, nullable=true) 
        @ORM\OneToOne(targetEntity="Travel\HomeBundle\Entity\Client")
        @ORM\JoinColumn(name="travel_access_token", referencedColumnName="secret")
  
       */
  
      protected $travel_access_token;
  
  
  
  
      public function __construct()
      {
          parent::__construct();
          // your own logic
      }
  
  
  }
  
  ?&gt;
  </code></pre>
  
  <p>after updating schema when i run following command to generate getter and setter methods </p>
  
  <pre><code>php app/console doctrine:generate:entities Travel/HomeBundle/Entity/User.php
  </code></pre>
  
  <p>i am getting following <code>Runtime Error</code></p>
  
  <pre><code> Namespace "Travel\HomeBundle\Entity\User.php" does not contain any mapped  
     entities.
  </code></pre>