Relax factories vs fixtures rule

[pirj]

Fixtures as something created before suite might be useful, specifically e.g. for a list of countries that are later used by other records (via say, user.country_id especially when there's a foreign key constraint).
There should be a balance between creating all the records, as this may negatively impact the performance when only a few examples are run vs save big when multiple examples are run.

Unfortunately, in Rails, the Rails fixtures are being loaded before each example, and that neglects the benefits, even despite the recently introduced bulk loading.