Use atty crate instead of libc

[ids1024]

This avoids direct use of anything platform specific, and is a reduction in code (not counting the generated Cargo.lock).

[ids1024]

The specific reason for this is to make the crate run on Redox OS (it is needed as a dependency of something). And it just generally seems like a good idea.

@banyan Does this seem reasonable?

[ids1024]

Ping @banyan; I'd like to get a program (specifically uutils) that uses this library to run on Redox without modifying Cargo.toml. Tell me if you'd prefer a different way to get it running on Redox.

[banyan]

@ids1024

sorry for late and thanks for the changes! 🙇

[banyan]

@ids1024

Released as 0.2.1!

[ids1024]

Thanks!

[ids1024]

Uh, crates.io still says last updated "10 months ago", and the download doesn't seem to have this change.

[banyan]

@ids1024

oh, sorry. I'll fix now.

[banyan]

sorry, I had to use cargo publish. Now uploaded as 0.2.2: https://crates.io/crates/pretty-bytes
🙇