grep out the homework/quiz/exam-problem-in relation

[kohlhase]

In ALeA we want to have the relation: problem A occurs in exam B for the various exams in MathHub/courses/FAU//hwexam/....tex

I believe that it should be possible to grep out this relation (or at least enough of it, so that we can limp along until the next semester where Dennis' new system is operational) so that we can build a classifier for the Practice problems that add labels like "homework problem", or "Exam 2019" to them.

The idea is to

• automatically see if a file in hexam/.../*.tex is actually a top-level exam.
• give it an ID and metadata (date, which course, retake or exam, ...)
• link all the imported problem URIs to this via triples.
• report all of this probably as RDF to Abhishek (negotiate with him what he needs).

assigned to myself, so that I do not disturb Frederik in his vacation.