removed relative_url_root for staging environment.

The app can be accessed now via port 3000 instead of a subdirectory.

config/environments/staging.rb

@@ -99,6 +99,5 @@ Rails.application.configure do
   config.active_record.dump_schema_after_migration = false
 
   # Run on subfolder in production environment.
-  config.relative_url_root = '/co-staging'
+  # config.relative_url_root = '/co-staging'
-
 end