def run(command, args = nil)
      cmd = CommandLine.new(command, args)
      vputs(cmd)
      cmd.run
    end
def run(command, args = nil)
      cmd = CommandLine.new(command, args)
      vputs(cmd)
      cmd.run
    end
Run an external command. Raise Error if something goes wrong. The
 command will be echoed if verbose?.

 Usage is similar to Kernel#system. If +args+ is nil, +command+ will be
 passed to the shell. If +args+ are included, the +command+ and +args+
 will be run directly without the shell.