With suggestions from helpful #rust folk. Thank you!

Yeah, I broke my own code again.

Also, re-use the stat result from directory-checking.

This finally fixes the issue where trying to list a file causes a crash. Also, tidy up some of the uses of references.

- Remove uses of to_string() on a &str where it wasn't necessary
- Use SendStr to reduce allocations further

I'm not sure if this a Rust change or something I've introduced...

What a strange bug to happen

The language keeps changing when I'm not looking!

I truly didn't realise this wasn't already done until someone sent me a .BMP file.

Also, rename old 'lines' view to 'details' which makes more sense

Grid view

- Lifetime changes in unix.rs
- lexical_ordering -> cmp
- from_utf8_lossy got moved into String
- vec.get(n) -> vec[n]

Fix build with rust master