title: check if a date is older that the current time in Rails
body: <p>I am doing a validations in my model to check if a date is older than today (meaning a date can only be in future from the current time)</p>
  
  <p>I was about to write down a block of code, but was wondering is there a build in function for this.</p>
  
  <p>The date is passed from a view using: </p>
  
  <pre><code>&lt;%= date_select ('load', :valid_until, :order =&gt; [:day, :month, :year]) %&gt;
  </code></pre>
  
  <p>All ideas are appreciated.</p>