Change log update

Author: michaelklishin

CHANGELOG.md

@@ -12,6 +12,9 @@
    used by `rabbitmqctl` and the latter reflects the fact that the command can be used to update an existing policy,
    in particular, to override its definition
  * `policies patch` is a new command that updates a policy definition by merging the provided definition with the existing one
+ * `policies declare_override` is a new command that declares a policy that overrides another policy
+ * `policies declare_blanket` is a new command that declares a low priority policy that matches all objects not matched
+   by any other policies
  * `parameters list_all` is a new command that lists all runtime parameters across all virtual hosts
  * `parameters list_in` is a new command that lists runtime parameters of a given component (type)
    in a specific virtual host