base_spec_helper now defines configs that are universal, whereas spec_helper is for configs that are using DatabaseCleaner and Selenium. This means we can include the base_spec_helper in both the system test setup and the regular setup but separate the other configurations for each type.
We want to enable instance managers to upload TOS files.
I also added the rails_helper which is a new convention. It can contain
more Rails specific configuration we currently have in the spec_helper.