def new_columns(columns)
      columns.each do |column|
        new_column(column[:type], column[:label], column[:id], column[:role], column[:pattern])
      end
    end
Adds multiple columns to the data_table.

Parameters:
* columns         [Required] An array of column objects {:type, :label, :id, :role, :pattern}. Calls new_column for each column object.