19版本的库（源代码，支持win:msvc&linux:gcc，单线程）。
Version 19 library (source code, support win:msvc&linux:gcc, single thread).
这个库是单线程的，移除了多线程代码，因为多线程依赖其他库。我只需要一个独立版本。
This library is single-threaded, and the multi-threaded code is removed, because multi-threading depends on other libraries. I just need a standalone version.
已经通过测试的编译环境如下：
The compiled environment that has passed the test is as follows:
1：windows10 mscv19
2：centos7 gcc4.8.5
拷贝到项目路径下。
Copy to the project path