code: void insert(Suffix<I, S> suffix) {
          if (activePoint.isNode()) {
              Node<I, S> node = activePoint.getNode();
              node.insert(suffix, activePoint);
          } else if (activePoint.isEdge()) {
              Edge<I, S> edge = activePoint.getEdge();
              edge.insert(suffix, activePoint);
          }
      }
docs: Inserts the given suffix into this tree.
  
  @param suffix The suffix to insert.