Eliminate more ActiveRecord-isms.
Introduce castanet-testing for, uh, CAS testing.
Start up CAS infrastructure in Travis CI.

It's not yet needed, but will be once I get Pancakes onto CAS.  (I'd
rather just deal with the CAS bits in all environments, since Pancakes
is really quite useless without CAS functionality.)

A similar set of incantations will be required for NUBIC's CI server.
I should just make them a single shell script.