io: Add Changelog

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.

io/CHANGELOG.md

@@ -0,0 +1,15 @@
+# 0.1 - Initial Release - 2023-01-18
+
+Create the `io` crate, add basic I/O traits, types, and implementations.
+
+Traits:
+
+- `Read`
+- `BufRead`
+- `Write`
+
+Types:
+
+- `Take`
+- `Cursor`
+- `Sink`