Icon Request: 思维导图
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## Icon Request

* Icon name:  mindmap
* Tags of this icon: mindmap
* Use case: 思维导图
* Screenshots of similar icons:
<img width="279" alt="截屏2020-04-23 10 25 40" src="https://user-images.githubusercontent.com/13865581/80052239-cbb70780-854c-11ea-9314-90087f1f3d30.png">
