- Fix C++17 Visual Studio builds.
- Use C++17 for `windows-2019` builds.
- Removed options for unsupported compiler (MSVC11).
- Removed options, not needed after enabling C++11+ features in gmock/gtest.
Problem:
- Both Windows builds test C++14
Solution:
- Use C++11 for `windows-2016` builds and C++14 for `windows-2019`
builds.
Co-authored-by: Jonathan Gopel <jgopel@quantlab.com>