Since on Windows HANDLEs are not the same as file descriptors,
confusing the two meant that almost all APIs in libuv had to go through
a thin compatibility layer, adding needless complication.
This removes that layer of external indirection and instead
works with the native Win32 API directly.
See: https://github.com/libuv/leps/blob/master/005-windows-handles-not-fd.md
PR-URL: https://github.com/libuv/libuv/pull/1166
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
