def outline_level_rows(start_index, end_index, level = 1, collapsed = true)
      outline rows, (start_index..end_index), level, collapsed
    end
shortcut level to specify the outline level for a series of rows
Oulining is what lets you add collapse and expand to a data set.
@param [Integer] start_index The zero based index of the first row of outlining.
@param [Integer] end_index The zero based index of  the last row to be outlined
@param [integer] level The level of outline to apply
@param [Integer] collapsed The initial collapsed state of the outline group