Add a CHANGELOG

Author: neilmayhew

CHANGELOG.md

@@ -0,0 +1,23 @@
+# Changelog
+
+Version history for `cardano-ledger-release-tool`
+
+## 0.1.1.0
+
+### changelogs
+
+* Improve error reporting
+  - Catch and report IO exceptions
+  - Exit with a failure if exceptions or errors occurred
+* Stop appending an extra blank line when writing to stdout
+* Add `--version` options to main and subcommands
+
+## 0.1.0.0
+
+* Restructure as a single `cardano-ledger-release-tool` app with subcommands
+
+## 0.0.0.0
+
+### changelogs
+
+* Initial release of the `changelogs` app