def list_and_select_op_script
      puts "List of available operational scripts:"
      puts "------------------------------------------------------------"
      for i in 0..@op_scripts.length - 1
        puts "  %3d. #{@op_scripts[i][0]}" % i
      end
      puts "------------------------------------------------------------"
      while true
        printf "Type the number of the script to run and press Enter (Ctrl-C to quit): "
        script_id = Integer(gets.chomp) rescue -1
        if script_id >= 0 && script_id < @op_scripts.length
          puts "Script choice: #{script_id}. #{@op_scripts[ script_id ][0]}"
          break
        else
          puts "#{script_id < 0 ? 'Invalid input' : 'Input out of range'}."
        end
      end

      return script_id
    end
def list_and_select_op_script
      puts "List of available operational scripts:"
      puts "------------------------------------------------------------"
      for i in 0..@op_scripts.length - 1
        puts "  %3d. #{@op_scripts[i][0]}" % i
      end
      puts "------------------------------------------------------------"
      while true
        printf "Type the number of the script to run and press Enter (Ctrl-C to quit): "
        script_id = Integer(gets.chomp) rescue -1
        if script_id >= 0 && script_id < @op_scripts.length
          puts "Script choice: #{script_id}. #{@op_scripts[ script_id ][0]}"
          break
        else
          puts "#{script_id < 0 ? 'Invalid input' : 'Input out of range'}."
        end
      end

      return script_id
    end
Presents the user with a list of scripts contained in @op_scripts
 and Returns an integer indicating the selection