Feature #8508: Use C++20's time zone support in std::chrono by default if supported.
Add the option to use std::chrono's date and time zone support
Before we can use it by default when the appropriate version of C++ is used, let's already add it as an option.
This should work with Visual Studio 2019 version 16.10 when
-DCMAKE_CXX_STANDARD=20 is used.