This is a big one. This change converts all of the existing tests from test/unit to RSpec. It's been a long time coming, and was specifically prompted by the inability of minitest to work with Appraisal across the various Rails versions. Instead of ironing out that headache, converting to RSpec was preferable (after initial probing). Many assertions are still assertions and are housed in the Assertions module, but they should be converted as they get touched. Similarly, since we're touching all the tests/specs, we convert all the hashes from 1.8 syntax to 1.9 syntax.