Add test coverage to show that when a getter references an overriden value.  Resolves #157.

The overridden value is returned.

        That is, confirming that the value returned by the getter is
       resolved at call-time, not declaration-time.

        The test I really care about here is how dbString gets resolved.

        The other tests are updated because of the interdependent and
       cascading relationship between the configuration values.

        Note that while these tests pass, when the tests are made to
       /fail/ for me, node crashes instead instead of the test
       returning false, the error is:

        "RangeError: Maximum call stack size exceeded".