moves the new :nsec date format to the Active Support changelog [ci skip]

activerecord/CHANGELOG.md

@@ -327,16 +327,11 @@
     *Yves Senn*
 
 *   Add `ActiveRecord::Base.cache_timestamp_format` class attribute to control
-    the format of the timestamp value in the cache key.
-    This allows users to improve the precision of the cache key.
+    the format of the timestamp value in the cache key. Defaults to `:nsec`.
     Fixes #8195.
 
     *Rafael Mendonça França*
 
-*   Add `:nsec` date format. This can be used to improve the precision of cache key.
-
-    *Jamie Gaskins*
-
 *   Session variables can be set for the `mysql`, `mysql2`, and `postgresql` adapters
     in the `variables: <hash>` parameter in `database.yml`. The key-value pairs of this
     hash will be sent in a `SET key = value` query on new database connections. See also:

activesupport/CHANGELOG.md

 ## Rails 4.0.0 (unreleased) ##
 
+*   Add `:nsec` date format.
+
+    *Jamie Gaskins*
+
 *   ActiveSupport::Gzip.compress allows two optional arguments for compression
     level and strategy.