title: Check string with Parsley.js custom validator
body: <p>I want to check if textarea contains  a link. It doesn't need to be anything complicated, just checking for <code>http</code> or <code>www</code> is good enough for me.</p>
  
  <p>But this doesn't work and I don't get anything with <code>console.log();</code>
  How can I debug Parsley validator?</p>
  
  <p>I just want to check if value doesn't contain http then return true for validation pass.</p>
  
  <pre><code>    window.Parsley.addValidator('messageWithoutLink', {
          validateNumber: function(value, requirement) {
              console.log(value);
              if(value.indexOf("http") !== -1)
                  return value;
              else 
                  return false;
          },
          requirementType: 'string',
          messages: {
              en: 'No links allowed'
          }
      });
  
  &lt;textarea id="contact_message" name="message" required data-parsley-required-message="Obligatory message" data-parsley-message-without-link&gt;&lt;/textarea&gt;
  </code></pre>