Add www.example.com to config.hosts

This resolves a bunch of (6) test failures that were failing due to an error page that said:

  To allow requests to www.example.com, add the following to your environment configuration:
  config.hosts << "www.example.com"

spec/dummy/config/application.rb

@@ -60,6 +60,8 @@ class Application < Rails::Application
 
     # Version of your assets, change this if you want to expire all your assets
     config.assets.version = '1.0'
+
+    config.hosts << "www.example.com"
   end
 end