https://www.cnblogs.com/pinard/p/6140514.html
https://www.cnblogs.com/liuwu265/p/4690486.html
https://blog.csdn.net/wangqi880/article/details/49765673
https://www.zhihu.com/question/41354392
GDBT和XGBoost
原文：https://www.cnblogs.com/aaronhoo/p/9038342.html
