Add mention about ActiveRecord::Base::filter_attributes to the changelog entry

Also remove `# :nodoc:` for `ActiveRecord::Core::ClassMethods` in order
to show non-nodoc methods in that module on the api docs http://edgeapi.rubyonrails.org

activerecord/CHANGELOG.md

@@ -9,11 +9,16 @@
 
     *Darwin Wu*
 
-*   Configuration item `config.filter_parameters` could also filter out sensitive value of database column when call `#inspect`.
+*   Configuration item `config.filter_parameters` could also filter out
+    sensitive values of database columns when call `#inspect`.
+    We also added `ActiveRecord::Base::filter_attributes`/`=` in order to
+    specify sensitive attributes to specific model.
 
     ```
     Rails.application.config.filter_parameters += [:credit_card_number]
-    Account.last.inspect # => #<Account id: 123, credit_card_number: [FILTERED] ...>
+    Account.last.inspect # => #<Account id: 123, name: "DHH", credit_card_number: [FILTERED] ...>
+    SecureAccount.filter_attributes += [:name]
+    SecureAccount.last.inspect # => #<SecureAccount id: 42, name: [FILTERED], credit_card_number: [FILTERED] ...>
     ```
 
     *Zhang Kang*

activerecord/lib/active_record/core.rb

@@ -139,7 +139,7 @@ module ActiveRecord
       self.default_connection_handler = ConnectionAdapters::ConnectionHandler.new
     end
 
-    module ClassMethods # :nodoc:
+    module ClassMethods
       def initialize_find_by_cache # :nodoc:
         @find_by_statement_cache = { true => Concurrent::Map.new, false => Concurrent::Map.new }
       end
@@ -216,7 +216,7 @@ module ActiveRecord
         generated_association_methods
       end
 
-      def generated_association_methods
+      def generated_association_methods # :nodoc:
         @generated_association_methods ||= begin
           mod = const_set(:GeneratedAssociationMethods, Module.new)
           private_constant :GeneratedAssociationMethods
@@ -226,7 +226,7 @@ module ActiveRecord
         end
       end
 
-      # Returns columns which shouldn't be exposed while calling #inspect.
+      # Returns columns which shouldn't be exposed while calling +#inspect+.
       def filter_attributes
         if defined?(@filter_attributes)
           @filter_attributes
@@ -235,13 +235,13 @@ module ActiveRecord
         end
       end
 
-      # Specifies columns which shouldn't be exposed while calling #inspect.
+      # Specifies columns which shouldn't be exposed while calling +#inspect+.
       def filter_attributes=(attributes_names)
         @filter_attributes = attributes_names.map(&:to_s).to_set
       end
 
       # Returns a string like 'Post(id:integer, title:string, body:text)'
-      def inspect
+      def inspect # :nodoc:
         if self == Base
           super
         elsif abstract_class?
@@ -257,7 +257,7 @@ module ActiveRecord
       end
 
       # Overwrite the default class equality method to provide support for decorated models.
-      def ===(object)
+      def ===(object) # :nodoc:
         object.is_a?(self)
       end