catalog boost

boost文档看了一遍，感觉“Libraries Listed by Category”一节对boost的分类不适合理解boost的组成，便根据自己的理解重新分了一下类：

1，Standalone Library for Applications:
graph, thread, python, mpl, preprocessor, math...

把math放在这儿有点勉为其难

2，Complement Library for STL:
Container:
array, multi_array, dynamic_bitset, property_map...
Iterator:
iterator_adapters...
Functor:
bind, compose, function, functional, lambda...

3，Generic Concept for Developer:

call_traits, type_traits, concept_check, static_assert,
base from member, chain of base...

这几个库或概念对代码本身的意义大于对代码实现功能的意义

4，utility:
all kind of cast, all kind of string parser, regex,
filesystem,datetime,any, smart_ptr, tuple, timer, test,
operators, io_state_saver, random, signals...

这一部分是龙蛇混杂的一部分，不过不乏标准库候选者如smart_ptr等