rm action_mailer & action_resource from dummy_app

No need to load this as we are not using. Also clears up this error
after updating to rails4 for the dummy_app:
/usr/local/var/rbenv/versions/2.1.0/lib/ruby/gems/2.1.0/gems/railties-4.0.3/lib/rails/railtie/configuration.rb:95:in
`method_missing': undefined method `action_mailer' for
<Rails::Application::Configuration:0x007f86abbe9d10> (NoMethodError)

spec/dummy_app/config/application.rb

@@ -3,8 +3,8 @@
 # Pick the frameworks you want:
 # require "active_record/railtie"
 require "action_controller/railtie"
-require "action_mailer/railtie"
-require "active_resource/railtie"
+#require "action_mailer/railtie"
+#require "active_resource/railtie"
 # require "sprockets/railtie"
 # require "rails/test_unit/railtie"
 

spec/dummy_app/config/environments/test.rb

@@ -24,7 +24,7 @@
   # Tell Action Mailer not to deliver emails to the real world.
   # The :test delivery method accumulates sent emails in the
   # ActionMailer::Base.deliveries array.
-  config.action_mailer.delivery_method = :test
+  #config.action_mailer.delivery_method = :test
 
 
   # Print deprecation notices to the stderr