updated field names
updated rspec version requirement

the `skip` method was causing errors with old versions of rspec.
removed unused classes
fixed references to old field names
Adding titles and preferred_biola_email methods to the Employee concern. Added tests for those as well.
This should allow spec 3.0
:accepted_student should never show up in visible affiliations
WCMS-86
Changes to person model

I changed `best_title` to `best_biola_title` since that is more
descriptive of what it is. I also changed the method `pref_name` to
`set_preffered_name` for the same reason.
Merge pull request #17 from biola/update_field_names

Update field names