ref https://mgleon08.github.io/blog/2016/08/30/optionparser/

require 'optparse'
class Help
  def initialize(arguments)
    @arguments = arguments
    @arguments = ["-h"] if @arguments == []
    parse_options
  end

  def parse_options
    options = OptionParser.new
    options.banner = 'Usage: Backup & Restore [options]'
    options.separator ''
    options.separator 'options:'
    options.on('-r', '--backup', 'backup') { backup }
    options.on('-r', '--restroe', 'restroe') { restroe }

    options.on('-h', '--help', 'Show this message') { puts(options); exit }
    options.parse!(@arguments)
  end
 end