def category_list
      response = Faraday.get("#{API_BASE}/categorylist")
      attributes = JSON.parse(response.body)
      result = Array.new
      attributes.each do |attrs|
        result << ListItem.new(attrs)
      end
      result
    end
def category_list
      response = Faraday.get("#{API_BASE}/categorylist")
      attributes = JSON.parse(response.body)
      result = Array.new
      attributes.each do |attrs|
        result << ListItem.new(attrs)
      end
      result
    end
returns an array of ListItem objects of categories