build: Update msvc build to use ISO standard C++17 #19445

This PR adds a compiler option to the msvc build to specify ISO C++17 support as discussed in #16684.

In order to allow Bitcoin Core to compile with the new option two pre-processor defines are also necessary to avoid an warning (treated as an error) for C++17 deprecated features:

• _SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING
• _SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING

For anyone interested a sample compiler message for each of the warnings is shown below:

c:\Dev\github\sipsorcery_bitcoin\src\support\allocators\zeroafterfree.h(21,5): error C4996: 'std::allocator<_Ty>::const_pointer': warning STL4010: Various members of std::allocator are deprecated in C++17. Use std::allocator_traits instead of accessing these members directly. You can define _SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. [c:\Dev\github\sipsorcery_bitcoin\build_msvc\libbitcoin_qt\libbitcoin_qt.vcxproj]

c:\Dev\github\sipsorcery_bitcoin\src\fs.cpp(29,31): error C4996: 'std::codecvt_utf8_utf16<wchar_t,1114111,(std::codecvt_mode)0>': warning STL4017: std::wbuffer_convert, std::wstring_convert, and the <codecvt> header (containing std::codecvt_mode, std::codecvt_utf8, std::codecvt_utf16, and std::codecvt_utf8_utf16) are deprecated in C++17. (The std::codecvt class template is NOT deprecated.) The C++ Standard doesn't provide equivalent non-deprecated functionality; consider using MultiByteToWideChar() and WideCharToMultiByte() from <Windows.h> instead. You can define _SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. [c:\Dev\github\sipsorcery_bitcoin\build_msvc\libbitcoin_util\libbitcoin_util.vcxproj]

Approach ACK 2894e94d17e57dedad02ac34e217ab80bbd72ed6

ACK 2894e94d17e57dedad02ac34e217ab80bbd72ed6

I think it's fine to disable the deprecation warnings for now, and maybe address them in a future PR. FWIW, <codecvt> seems to be only used on Windows, so the suggested fix to use MultiByteToWideChar() and WideCharToMultiByte() would work. These functions are even already used in some places (fs.cpp and leveldb).