class Prawn::Table::Cells

each cell, grouped by +row_or_column+.
Takes the min/max (per +aggregate+) of the result of sending +meth+ to
Sum up a min/max value over rows or columns in the cells selected.

def aggregate_cell_values(row_or_column, meth, aggregate)
  ColumnWidthCalculator.new(self).aggregate_cell_values(row_or_column, meth, aggregate)
end