modified
Merge branch 'master' of https://github.com/LukeLin/data-structure-with-js
Merge branch 'master' of https://github.com/LukeLin/data-structure-with-js
Merge branch 'master' of https://github.com/LukeLin/data-structure-with-js
修复BBSTNode.prototype.insert()的循环引用导致的bug，给api添加文档注释