Fine-grained error messages for remove_dir_all

[andrewhickman]

The standard library implements remove_dir_all in terms of multiple operations. We should provide an error message detailing exactly which of these failed.

This is straightforward on most platforms. The implementation can be replicated using existing APIs. Unfortunately the windows implementation uses the unstable FileTypeExt::is_symlink_dir

We can work around this by using winapi directly, or waiting for the method to stabilize

[LPGhatguy]

It looks like you closed this in f61ae29

I noticed after pulling from master and being surprised, I didn't read this commit on GitHub because of its message! 😅

[LPGhatguy]

Actually, it looks like that commit broke building on Windows and might've been unintentional. Do we want to back it out?

[andrewhickman]

That was indeed unintentional, thanks for pointing it out 😄

[andrewhickman]

FileTypeExt::is_symlink_dir is stable as of Rust 1.64.0. It would be a shame to impose a MSRV just for this, but maybe this could be implemented as an optional feature