When inspecting previously-generated files, a new `Test` instance should
be used. This avoids over-writing the in-memory representation of the
latest test, and allows previously-existing test files to be partially
updated according to subsequent changes in their respective source/case
files.
In expecting "case directories" to contain a sub-directory named
"default", the test generation tool is unable to generate tests for
features where a directory named "default" is not appropriate.
Modify the heuristic that identifies "case directories" to use a more
fundamental aspect (i.e. the existence of at least one "case" file).
Leo Balter
jugglinmike