title: Possible to validate only if certain radio button is selected?
body: <p>I have two radio buttons at the end of my form, "Yes" and "No". Currently it validates the user input no matter whether a user selects "Yes" or "No".</p>
  
  <p>I would like to validate the input only if he selects "Yes", and display an error message in case he selects "No". Is that possible with ParsleyJS? </p>
  
  <p>I don't know if it is important to mention but I've integrated ParsleyJS only by using data-attributes. I'm not using custom jQuery or JavaScript for the form validation.</p>
  
  <p>Thanks for your help! </p>