title: create checkbox with customise label in symfony
body: <p>I have a simply problem. 
  I want just to create a checkbox widget with symfony so: </p>
  
  <pre><code> $builder-&gt;add("terms", CheckboxType::class, array('label'=&gt;false));
  </code></pre>
  
  <p>But i obtain this output: </p>
  
  <pre><code>&lt;div class="checkbox"&gt;
      &lt;label for="fos_user_registration_form_terms" class="required"&gt;
          &lt;input id="fos_user_registration_form_terms" name="fos_user_registration_form[terms]" required="required" class=" checkbox" value="1" type="checkbox"&gt;
                          Terms
       &lt;/label&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I want change text of label but when override the label attribut in PHP the output is: </p>
  
  <pre><code>&lt;div class="checkbox"&gt;
      &lt;label for="fos_user_registration_form_terms" class="required"&gt;
          &lt;div class="checkbox"&gt;
              &lt;label for="fos_user_registration_form_terms" class="required required"&gt;
                &lt;input id="fos_user_registration_form_terms" name="fos_user_registration_form[terms]" required="required" class=" checkbox" value="1" type="checkbox"&gt;
                          test
               &lt;/label&gt;
          &lt;/div&gt;
          test
       &lt;/label&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I have two label. </p>
  
  <p>I will want obtain: </p>
  
  <pre><code>&lt;div class="checkbox"&gt;
  &lt;label for="fos_user_registration_form_terms" class="required"&gt;
      &lt;input id="fos_user_registration_form_terms" name="fos_user_registration_form[terms]" required="required" class=" checkbox" value="1" type="checkbox"&gt;
                  My label for accept terms with &lt;a&gt; tag   
  
   &lt;/label&gt;
  </code></pre>
  
  <p></p>
  
  <p>I use this <a href="http://bootstrap.braincrafted.com/getting-started.html" rel="nofollow">bundle</a> (BraincraftedBootstrapBundle)</p>
  
  <p>Thank you for your help. </p>