Tweak 0.23 notes and add another test for events (#618)

* Tweak 0.23 notes and add another test for events

* Address new Eq clippy lint

examples/examples/custom_type_derives.rs

@@ -11,7 +11,7 @@
     // a comma separated list to the below attribute. Most useful for adding `Clone`.
     // The derives that we can add ultimately is limited to the traits that the base
     // types relied upon by the codegen implement.
-    derive_for_all_types = "Clone, PartialEq",
+    derive_for_all_types = "Clone, PartialEq, Eq",
 
     // To apply derives to specific generated types, add a `derive_for_type` per type,
     // mapping the type path to the derives which should be added for that type only.