Rename release notes directory for correctness

(Grumble docs wrong grumble grumble)

release/0.2.0+1.9

@@ -0,0 +1,11 @@
+When upgrading to 1.9, you'll need to update your app(s') configuration(s) for
+new settings names:
+
+- Rename `AUTH_RATELIMIT` to `AUTH_RATELIMIT_IP`
+- Add MESSAGE_RATELIMIT (default `200/day`)
+- Add `TZ` to specify server timezone, e.g. `TZ=Etc/UTC`
+- Remove `PASSWORD_SCHEME`
+- Add `CREDENTIAL_ROUNDS` (default `12`)
+
+If you haven't made these changes already, it's best to bail on this upgrade
+FIRST (i.e. Ctrl+C) and run `abra app config` first.