Replacing spec_slow_helper

Once upon a time the slow helper was only 2x slower. Now for the
changed file I have the following:

With spec_slow_helper:
`Finished in 0.16608 seconds (files took 2.75 seconds to load)`

With spec_active_record_helper:
`Finished in 0.0954 seconds (files took 0.6944 seconds to load)`