title: Javascript: Regular expression for time format HH:MM
body: <p>Hi I want to validate a string to check f it has valid time format. <code>HH:MM</code>
  However,(due to some insane business reasons) I also want to validate <code>24:00</code> as correct. </p>
  
  <p>The following works <code>{([0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]}</code> but does not validate <code>24:00</code>. </p>