…ck<std::mutex>, leading to two mutexes used in condition_variable_t

Solution: use std::condition_variable_any instead

Solution: calculate from CMAKE_SYSTEM_VERSION

Problem: CMAKE_SYSTEM_VERSION might be newer than Windows SDK Version

Solution: limit _WIN32_WINNT value to Visual Studio default Windows SDK version

…g and not configurable

Solution: move configuration to build definition

…newer due to duplicate definition of htonll

Solution: use custom implementation only on older Windows versions

Solution: change variable type to size_t

Solution: change into regular control flow condition