Document caches_action. Closes #5419.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6787 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/CHANGELOG

 *SVN*
 
+* Document caches_action.  #5419 [Jarkko Laine]
+
 * Update to Prototype 1.5.1.  [Sam Stephenson]
 
 * Allow routes to be decalred under namespaces [Tobias Luetke]: 

actionpack/lib/action_controller/caching.rb

@@ -180,7 +180,9 @@ def self.included(base) #:nodoc:
         base.send(:attr_accessor, :rendered_action_cache)
       end
 
-      module ClassMethods #:nodoc:
+      module ClassMethods
+        # Declares that +actions+ should be cached.
+        # See ActionController::Caching::Actions for details.
         def caches_action(*actions)
           return unless perform_caching
           around_filter(ActionCacheFilter.new(*actions))