title: jQuery inputmask allowing placeholder text to remain
body: <p>I am using the inputmask from <a href="https://github.com/RobinHerbots/jquery.inputmask" rel="noreferrer">https://github.com/RobinHerbots/jquery.inputmask</a> and applying the mask to all textboxes with class "date".  The problem I am having is that if the user leaves one or more of the letters from the placeholder in place, it will be accepted.  For example, the user enter 10 but then clicks out of the field and the field is left with 10/dd/yyyy.  How can I stop this behavior?  I want to prevent the user from leaving the field when it looks like this.</p>
  
  <p>here is the jQuery for the mask:</p>
  
  <pre><code>$('.date').inputmask("mm/dd/yyyy", { "placeholder": "mm/dd/yyyy" })
  </code></pre>