title: Jquery/Javascript timer that doesn't restart on refresh
body: <p>this is my first question on SO :)</p>
  
  <p>I need a timer in jQuery or javascript that will countdown 15 minutes, and than show a close button. Also, when user refreshes the page it should not reset, but either continue where it stopped or finish countdown not depending on whether user came back, i.e. if the user returns after 16 minutes, he will see message and a close button.  Any suggestions? </p>
  
  <p>THANK YOU VERY MUCH!</p>