lstat implementation on windows

[lbonn]

Link and symlink capabilities exist on win32 platform, yet lstat's implementation is still missing.

Some fs operations need it to work properly, for example rmdir_recursive (#12573)

[lbonn]

After a little search, I noticed that rust is an outlier by trying to support links on windows: python and golang don't provide link functions and alias lstat to stat.

However, libuv looks interesting in this regard:
https://github.com/joyent/libuv/blob/1dc2709b999a84520ab1b3c56c0e082bf8617c1f/src/win/fs.c#L971

[steveklabnik]

src/libstd/sys/unix/fs2.rs:pub fn lstat(p: &Path) -> io::Result<FileAttr> {

Seems to exist now. 🎊