code: private String formatNodeLabel(PatriciaTrie.PatriciaNode<V> node, KeyMapper<String> keyMapper,
                      boolean formatBitString) {
          StringBuilder builder = new StringBuilder();
          builder.append("<<table border=\"0\" cellborder=\"0\">");
          // Key
          builder.append("<tr><td>");
          builder.append("key: <font color=\"#00a000\">");
          builder.append(getNodeLabel(node));
          builder.append("</font> </td></tr>");
  
          // Critical bit
          builder.append("<tr><td>");
          builder.append("bit: <font color=\"blue\">");
          builder.append(node.getBit());
          builder.append("</font> </td></tr>");
  
          // Bit string
          if (formatBitString) {
              builder.append("<tr><td>");
              builder.append("bitString: <font color=\"blue\">");
              String bitString = keyMapper.toBitString(node.getKey());
              int c = node.getBit() + node.getBit() / 4;
              builder.append(bitString.substring(0, c));
              builder.append("<font color=\"red\">");
              builder.append(bitString.charAt(c));
              builder.append("</font>");
              builder.append(bitString.substring(c + 1));
              builder.append("</font> </td></tr>");
          }
  
          // Value
          builder.append("<tr><td>");
          builder.append("value: <font color=\"#00a0a0\">");
          builder.append(node.getValue());
          builder.append("</font> </td></tr>");
  
          builder.append("</table>>");
          return builder.toString();
      }
docs: Format node label
  
  @param node  node to format
  @param keyMapper  keymapper to map keys to bits
  @param formatBitString  true if the bits for this key should be included in the node
  @return formatted node, not null