通过 `happy` 可以自定义配置表情图片。
默认值为：
```
[
'http://wangeditor.github.io/expressions/1.gif',
'http://wangeditor.github.io/expressions/2.gif',
'http://wangeditor.github.io/expressions/3.gif',
'http://wangeditor.github.io/expressions/4.gif',
'http://wangeditor.github.io/expressions/5.gif',
'http://wangeditor.github.io/expressions/6.gif',
'http://wangeditor.github.io/expressions/7.gif',
'http://wangeditor.github.io/expressions/8.gif',
'http://wangeditor.github.io/expressions/9.gif',
'http://wangeditor.github.io/expressions/10.gif',
'http://wangeditor.github.io/expressions/11.gif',
'http://wangeditor.github.io/expressions/12.gif',
'http://wangeditor.github.io/expressions/13.gif',
'http://wangeditor.github.io/expressions/14.gif',
'http://wangeditor.github.io/expressions/15.gif',
'http://wangeditor.github.io/expressions/16.gif',
'http://wangeditor.github.io/expressions/17.gif',
'http://wangeditor.github.io/expressions/18.gif',
'http://wangeditor.github.io/expressions/19.gif',
'http://wangeditor.github.io/expressions/20.gif'
]
```
- 全局配置示例：
```
___E.config.happy = [
'img/1.gif',
'img/2.gif',
'img/3.gif'
]
```
- 对象配置示例：
```
editor.config.happy = [
'img/1.gif',
'img/2.gif',
'img/3.gif'
]
```
