Add a short changelog

nicholasbishop · phip1611 · commit df20dc652f5c · 2024-03-25T09:49:36.000+01:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Unreleased
+
+* Impl `Display`, `Eq`, `PartialEq`, `Ord`, `PartialOrd`, and `Hash` for
+  the `Error` type.
+* Switch to the 2021 edition.
