title: How can I add a repeated type field in easy admin bundle
body: <p>I'm trying to add a password repeat using easy admin bundle but I'm not quite sure how to do it. 
  I have these two properties in my entity</p>
  
  <pre><code>/**
   * @var string
   *
   * @Assert\NotBlank()
   * @Assert\Length(max="4096")
   */
  private $plainPassword;
  
  /**
   * @var string
   *
   * @ORM\Column(type="string", length=64)
   */
  private $password;
  </code></pre>
  
  <p>If I add a type: repeated in my config.yml file it just creates two input fields but not a Password type. I believe form should be like this.</p>
  
  <pre><code>public function buildForm(FormBuilderInterface $builder, array $options)
  {
      $builder
          -&gt;add('email', EmailType::class)
          -&gt;add('username', TextType::class)
          -&gt;add('plainPassword', RepeatedType::class, array(
              'type' =&gt; PasswordType::class,
              'first_options'  =&gt; array('label' =&gt; 'Password'),
              'second_options' =&gt; array('label' =&gt; 'Repeat Password'),
              )
          )
          -&gt;add('termsAccepted', CheckboxType::class, array(
              'mapped' =&gt; false,
              'constraints' =&gt; new IsTrue(),
          )
      );
  }
  </code></pre>
  
  <p>I have checked the easy admin bundle documentation but I'm kinda lost how to implement it. <a href="https://github.com/javiereguiluz/EasyAdminBundle/blob/master/Resources/doc/book/7-complex-dynamic-backends.md" rel="nofollow">https://github.com/javiereguiluz/EasyAdminBundle/blob/master/Resources/doc/book/7-complex-dynamic-backends.md</a></p>
  
  <p>Thanks</p>
  
  <ul>
  <li><p>Edit
  Okay so I extended the AdminController of <code>JavierEguiluz\Bundle\EasyAdminBundle\Controller\AdminController</code></p>
  
  <pre><code>public function createNewForm($entity, array $entityProperties)
  {
      $userForm = parent::createNewForm($entity, $entityProperties);
  
      if ($entity instanceof User) {
          $userForm-&gt;remove('password');
          $userForm-&gt;add('plainPassword', RepeatedType::class, array(
              'type' =&gt; PasswordType::class,
              'first_options' =&gt; array('label' =&gt; 'Password'),
              'second_options' =&gt; array('label' =&gt; 'Re-enter Password')
          ));
      }
  
      return $userForm;
  }
  </code></pre></li>
  </ul>
  
  <p>But now when I try to insert / submit the form, sql error password cannot be null.</p>