always forget the changelog

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4266 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

 *SVN*
 
-* Raise error when trying to add to a has_many :through association. [Rick]
+* Raise error when trying to add to a has_many :through association.  Use the Join Model instead. [Rick]
 
     @post.tags << @tag                  # BAD
     @post.taggings.create(:tag => @tag) # GOOD