This adds MSVC builds built on Linux using wine. This requires some settings of tools and flags because the autotools support for MSVC is naturally somewhat limited.
The advantage of this approach is that it is compatible with our existing CI scripts, so there’s no need to write a Windows CI script (in PowerShell or similar). If we want to test building and running on Windows native (e.g., as supported by Cirrus CI) we could still do this in the future.
Another advantage of this approach is that contributors can simply use the docker image if they need a MSVC installation in a non-Windows environment.