class Columnize::Columnizer

def opts=(opts)
  @opts = opts
  OLD_AND_NEW_KEYS.each {|old, new| @opts[new] = @opts.delete(old) if @opts.keys.include?(old) and !@opts.keys.include?(new) }
  @opts.merge!(ARRANGE_ARRAY_OPTS) if @opts[:arrange_array]
  set_attrs_from_opts
end