版本：2.7.2
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/flexslider.css
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/flexslider.min.css
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/fonts/flexslider-icon.svg
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/images/bg_play_pause.png
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/jquery.flexslider-min.js
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/jquery.flexslider.js
- https://cdn.bootcdn.net/ajax/libs/flexslider/2.7.2/jquery.flexslider.min.js