Added question_ids to "details" in grading info and to the "__results" property
All of test-items is name-based to support input/export from different OpenACS instances. In some situations, it is still necessary to pinpoint the origin of questions, e.g. when importing pool-questions to an external gradebook, where e.g. one wants to associate a replacement questions with the original pool question.
Now we keep an additional question id, which will point to the pool question or the simple question together with the question names. The instance attribute "__results" is set once the exam-protocol was rendered completely.