title: How to set a delay for L.Tooltip display?
body: <p>I am wondering how to set a delay for tooltip visualization on mouse hover. I haven't found such a feature in options description in docs.</p>
  
  <p>My map is crowded with many markers, so when mouse is moving around, all the time some tooltips appear. My idea is to set some delay, so that for example after 1 second of hovering, tooltip for this particular marker to be displayed.</p>
  
  <p>Thank you!</p>