Single error when `--require`'d files fail to load

Created by: deivid-rodriguez

When there's an error loading files specified via the --require flag, typically rails_helper.rb or spec_helper.rb, it's very common that most of the spec files won't load either since they depend on the helper file being loaded. In these situations, one gets hundreds of errors printed to the screen. That can be quite intimidating and contributes to hide the real culprit, which is the load error in the helper.