版本：0.12.15
- https://cdn.bootcdn.net/ajax/libs/paper.js/0.12.15/paper-core.js
- https://cdn.bootcdn.net/ajax/libs/paper.js/0.12.15/paper-core.min.js
- https://cdn.bootcdn.net/ajax/libs/paper.js/0.12.15/paper-full.js
- https://cdn.bootcdn.net/ajax/libs/paper.js/0.12.15/paper-full.min.js