This adds a set of Visual Studio NMake Makefiles that can be used to
build libpsl, either as a DLL or as a static .lib. Building of the psl
tool and the tests in tests/ (but not fuzz, since those tests use
fmemopen(), that is not supported on Windows) are also supported.
A simplified "install" target is provided that copies the build
results to a default or set prefix with the pkg-config file so that
other packages (such as libsoup) with build systems that depend on this
.pc file can be built.
These files make use of autotools stuff so that they have the up-to-date
version info upon a release.
Currently, only builds using the ICU runtime/builtin or with no
runtime/builtin are supported with Visual Studio builds.
Chun-wei Fan