C++ 20 string, fast like Sonic :3

This small header only library defines a set of string.h adjacent methods that are implemented using SIMD and SWAR techniques.

It also defines a type Sonic::String. This type is a string type, designed to be highly customizable in its SSO optimizations.

cl /nologo /O2 /W4 /std:c++20 /arch:AVX2 .\sample.cpp .\second.cpp