code: public short getLevel(int nodeHandle) {
                  short count = 0;
                  while (nodeHandle != 0) {
                          count++;
                          nodeHandle = nodes.readEntry(nodeHandle, 1);
                  }
                  return count;
          }
docs: Get the depth level of this node in the tree (equals 1 for
  a parentless node).
  
  @param nodeHandle The node id.
  @return the number of ancestors, plus one
  @xsl.usage internal