def set_opts(opts)
      opts.banner = <<END
Usage: #{default_syntax} [options] [INPUT] [OUTPUT]

Description:
  Converts SCSS or Sass files to CSS.
END

      common_options(opts)
      watching_and_updating(opts)
      input_and_output(opts)
      miscellaneous(opts)
    end
def set_opts(opts)
      opts.banner = <<END
Usage: #{default_syntax} [options] [INPUT] [OUTPUT]

Description:
  Converts SCSS or Sass files to CSS.
END

      common_options(opts)
      watching_and_updating(opts)
      input_and_output(opts)
      miscellaneous(opts)
    end
Tells optparse how to parse the arguments.

 @param opts [OptionParser]