remove references to attr_accessible

Author: Jed Schneider

sites/curriculum/hooking_up_votes_and_topics.step

@@ -17,26 +17,12 @@ goals {
 }
 
 steps {
-  step 'Edit the Gemfile' do
-   message "In order to save votes through the Topic model we must allow Rails to whitelist specific attributes for each model."
-   message "In Rails 4, this functionality is provided in a separate gem. We need to install that gem in order to save the votes."
-   message "Open the `Gemfile` in your text editor. Under the declaration for the `rails` gem add the following line of code:"
-
-    source_code :ruby, <<-RUBY
-gem 'strong_parameters'
-    RUBY
-  end
-
-  step "Apply the Gemfile changes" do
-    console "bundle install"
-  end
 
   step {
     message "Edit `app/models/topic.rb` so that it looks like this:"
 
     source_code :ruby, <<-RUBY
 class Topic < ActiveRecord::Base
-  attr_accessible :description, :title
   has_many :votes, dependent: :destroy
 end
     RUBY
@@ -46,7 +32,6 @@ end
     message "Edit `app/models/vote.rb` so that it looks like this:"
     source_code :ruby, <<-RUBY
 class Vote < ActiveRecord::Base
-  attr_accessible :topic_id
   belongs_to :topic
 end
     RUBY