add a required field to custom fields type

ref Chill-project/Chill-CustomFields#17

Form/CustomFieldType.php

@@ -66,6 +66,11 @@ class CustomFieldType extends AbstractType
         
         $builder
             ->add('ordering', 'number')
+            ->add('required', 'checkbox', array(
+                'required' => false,
+                //'expanded' => TRUE,
+                'label' => 'Required field'
+            ))
             ->add('type', 'hidden', array('data' => $options['type']))
             ->addEventListener(FormEvents::PRE_SET_DATA, function (FormEvent $event) 
             {

Form/Type/CustomFieldType.php

@@ -20,6 +20,7 @@ use Chill\CustomFieldsBundle\Service\CustomFieldProvider;
 use Chill\CustomFieldsBundle\Form\DataTransformer\CustomFieldDataTransformer;
 use Chill\CustomFieldsBundle\Entity\CustomFieldsGroup;
 use Symfony\Component\OptionsResolver\OptionsResolver;
+use Chill\CustomFieldsBundle\CustomFields\CustomFieldTitle;
 
 class CustomFieldType extends AbstractType
 {
@@ -50,6 +51,7 @@ class CustomFieldType extends AbstractType
             $this->customFieldCompiler
                 ->getCustomFieldByType($cf->getType())
                 ->buildForm($builder, $cf);
+            $builder->get($cf->getSlug())->setRequired($cf->isRequired());
         }
     }