版本：
文件：
- https://cdn.bootcdn.net/ajax/libs/merge-images/2.0.0/index.es2015.js
- https://cdn.bootcdn.net/ajax/libs/merge-images/2.0.0/index.es2015.min.js
- https://cdn.bootcdn.net/ajax/libs/merge-images/2.0.0/index.umd.js
- https://cdn.bootcdn.net/ajax/libs/merge-images/2.0.0/index.umd.min.js