This has bothered me for awhile, but writing the hacking guide has
given me an opportunity to refactor some of our test-suite to be
simpler, more consistent, and easier to understand. This is
important if we want users to provide well-written tests. Our
test-suite is an important part of the code-base and it should be
easy to write good tests.
Basically I just consolidated CoreUnitTestCase, UnitTestCase, and
ServiceTestBase into a single class named ServiceTestBase. I also
simplified some of the configuration creation methods to reduce
duplicated code.