We attempted to release with the current 0.1.0 version forgetting that
we had previously released an empty crate with that version to reserve
the name on crates.io.
Bump the version to 0.1.1 and release the actual code.
Done in preparation for an initial v0.1.0 release of the new `io` crate.
Add a changelog file with a brief description of whats in the initial release.