tokio-io is deprecated

[xbjfk]

Hello,
I was beginning to fork xz2 as well, until I came across this crate, thanks for maintaining it!

According to its docs, it has been deprecated in favor of tokio::io.
I tried doing this and it made it seemed to be a non trivial migration, so it might be worth removing tokio entirely, like flate2-rs did: rust-lang/flate2-rs#292, as well as trifectatechfoundation/bzip2-rs#89 and alexcrichton#109.

It seems the recommended approach is the async-compression crate, which unfortunately uses xz2 still, but I have made a PR: Nullus157/async-compression#288.

Thanks!

[ChanTsune]

Hello @xbjfk !

Thank you for your message and suggestions. I will review the deprecation notice and consider the migration challenges.

Thanks again!