Rails 5 updates for job board curriculum

* quiet_assets is no longer needed (though we contrivedly
  talk about `bundle install` anyway)
* Different (worse?) errors for missing templates
* ApplicationRecord instead of active record
* Migrations have this version thing
* `null: false` is missing from timestamps in migrations

sites/en/job-board/create_a_rails_app.step

@@ -43,11 +43,11 @@ MARKDOWN
 
 discussion_box "Text Editor vs Command Line", "Review the differences between the the command line and your text editor, even if everyone already knows!"
 
-message "# Fix Up Those Defaults"
+message "# Let's Talk About Dependencies"
 
-source_code_with_message "We're going to be looking at the Rails server output, which includes a lot of noise by default. Find the file called 'Gemfile' by searching for it, and add the following line:", :ruby, "gem 'quiet_assets'"
+message "When we created a new Rails app, it installed a bunch of stuff by default. The list of things Rails installed is in a file called `Gemfile`. If you want to add any additional third party code (aka **gems**), you can add more lines to the `Gemfile` and install them with `bundle`."
 
-console_with_message "Save the file, and then in the command line, run the following command:", "bundle install"
+console_with_message "Rails has already installed all the stuff we need, but you can always run bundle again to re-install gems, or install gems newly added to the Gemfile. In the command line, run the following command:", "bundle install"
 
 discussion_box "What does 'bundle' do?", <<-MARKDOWN
  Bundler is the tool the Ruby community uses for dependency management.

sites/en/job-board/job-board.step

@@ -16,7 +16,7 @@ message <<-MARKDOWN
   We're also going to skip deploying to Heroku this time around, but you can definitely use the instructions from the Suggestotron curriculum to deploy your app to the internet!
 MARKDOWN
 
-important "This curriculum is written for Rails 4. Things will get awkward / broken if you're using Rails 3, so if you skipped the Installfest, you need to upgrade to Rails 4 now."
+important "This curriculum is written for Rails 5. Things will get awkward / broken if you're using an earlier version of Rails, so if you skipped the Installfest, you need to upgrade to Rails 5 now."
 
 message <<-MARKDOWN
   # Tips for everyone:

sites/en/job-board/listing_the_jobs.step

@@ -32,7 +32,7 @@ MARKDOWN
 
 message "# Show those jobs!"
 
-source_code_with_message "Add this to app/views/jobs/index.html.erb:", :ruby,
+source_code_with_message "Add this to app/views/jobs/index.html.erb:", :erb,
 <<-RUBY
   <% @jobs.each do |job| %>
     <h3><%= job.title %></h3>

sites/en/job-board/make_a_jobs_home_page.step

@@ -33,7 +33,7 @@ MARKDOWN
 source_code_with_message "We're going to need a resource route, which will create EIGHT different routes for us. Add this to line two:", :ruby, "resources :jobs"
 
 message <<-MARKDOWN
-  Now, lets go look at what that made, by using the excellently helpful page available on any Rails 4 app: <http://localhost:3000/rails/info>.
+  Now, lets go look at what that made, by using the excellently helpful routes page: <http://localhost:3000/rails/info>.
 MARKDOWN
 
 discussion_box "How to read the routes page.", <<-MARKDOWN
@@ -49,8 +49,6 @@ discussion_box "How to read the routes page.", <<-MARKDOWN
   Can you find the line that will make `/jobs` a route?
 MARKDOWN
 
-tip "If you are on Rails 3, going to /rails/info will **fail**! Stop right now and upgrade to Rails 4."
-
 message <<-MARKDOWN
   Since adding the line `resources :jobs` made a route matching `/jobs`, let's go visit that page again: <http://localhost:3000/jobs>
 MARKDOWN
@@ -97,10 +95,10 @@ RUBY
 
 message "And refresh <http://localhost:3000/jobs>"
 
-error_box "Missing template jobs/index, application/index with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :raw, :ruby, :jbuilder, :coffee]}. Searched in: * '/Users/probablyyou/railsbridge/job_board/app/views'"
+error_box "JobsController#index is missing a template for this request format and variant."
 
 message <<-MARKDOWN
-  What's the important part of the this error? How does Rails decide to look for something called jobs/index? How did it decide to look in the views directory?
+  What's a template? How does Rails decide to look for the template associated with JobsController's `index` action?
 
   Talk through what Rails is trying, and failing, to do, and how file names and method names are important here.
 

sites/en/job-board/make_the_form_work.step

@@ -24,9 +24,9 @@ source_code :ruby,
   end
 RUBY
 
-message "Reload the page!"
+message "Try to use your form again. Unfortunately, there won't be any output, not even an error page. But if you look closely at the output from your Rails server, you might find this:"
 
-error_box "Missing template jobs/create, application/create with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :raw, :ruby, :jbuilder, :coffee]}. Searched in: * '/Users/lillie/railsbridge/job_board/app/views'"
+error_box "No template found for JobsController#create, rendering head :no_content"
 
 <<-MARKDOWN
   Familiar error, right? We don't have a template called create.html.erb.
@@ -78,7 +78,7 @@ source_code :http,
 JSON
 
 message <<-MARKDOWN
-  This is the precious data that our form is sending, and right now we're just throwing it away. Let's not do that! Since we're using Rails 4 and all its great conventions, we're going to use Strong Parameters to limit what kind of data our form can submit to our app.
+  This is the precious data that our form is sending, and right now we're just throwing it away. Let's not do that! Since we're using Rails 5 and all its great conventions, we're going to use Strong Parameters to limit what kind of data our form can submit to our app.
 MARKDOWN
 
 source_code_with_message "Add this code to your jobs controller. (Notice that we're expanding the create method. Don't just copy and paste and end up with two create methods, folks.)", :ruby,

sites/en/job-board/store_jobs_in_the_database.step

@@ -35,11 +35,11 @@ message <<-MARKDOWN
 MARKDOWN
 
 source_code :ruby, <<-RUBY
-  class CreateJobs < ActiveRecord::Migration
+  class CreateJobs < ActiveRecord::Migration[5.0]
     def change
       create_table :jobs do |t|
 
-        t.timestamps null: false
+        t.timestamps
       end
     end
   end
@@ -55,7 +55,7 @@ source_code :ruby, <<-RUBY
   create_table :jobs do |t|
     t.text :title
     t.text :description
-    t.timestamps null: false
+    t.timestamps
   end
 RUBY
 

sites/en/job-board/update_job_listings.step

@@ -12,6 +12,8 @@ source_code_with_message "Say we want to edit the first job posting. If we look
 
 message "So, it looks like if we want to edit the job description, we should visit this URL: <http://localhost:3000/jobs/1/edit>."
 
+error_box "The action 'edit' could not be found for JobsController"
+
 source_code_with_message "We've seen this before, right? Let's add the controller action:",
 <<-RUBY
   def edit