title: Delete the last 2 additions to a featuregroup in Leaflet
body: <p>I have a featuregroup that adds circlemarkers and paths -- they are added in sequence and I need a way to create a function that will remove the last (2) in the _layers every time it's clicked.</p>
  <p>I tried slicing but that doesn't work because it's not really an array.</p>
  <p>Any thoughts on how to proceed? I've been searching stackoverflow for awhile and cannot find anything that matches what I'm trying to do.</p>