code: public TableLayoutBuilder separator(String labelKey, String attributes) {
          Cell cc = cellInternal(getComponentFactory().createLabeledSeparator(labelKey), attributes);
          lastCC = cc;
          items.add(cc);
          return this;
      }
docs: Inserts a separator with the given label. Attributes my be zero or more of
  rowSpec, columnSpec, colGrId, rowGrId, align and valign.
  
  @deprecated this is a layout builder, creating components should be done elsewhere, use cell() methods instead