impl Clone for DirEntry

[lunacookies]

Thanks for async_std :)

The sync version of DirEntry does not implement Clone, which is the reason why we didn't implement it either:
https://doc.rust-lang.org/nightly/std/fs/struct.DirEntry.html

But I suppose implementing Clone for our DirEntry wouldn't hurt. We can even derive the impl because our DirEntry wraps an Arc<std::fs::DirEntry>.

[lunacookies]

Sounds good!

[lunacookies]

Thanks.