The problem was with the non-UTF-8-safe way that a question name
was being constructed from the question text.
I have done a proper fix with methods in the base class to
carefully construct a question name that is reasonable, and
which will fit in the database column. Then I have changed all
importers to use the new methods.
I also remembered not to break the lesson in the process.
1/ type/match/tests/walkthrough_test.php - tests are failing randomly, looks like some weird randomisation is going on there - see TODOs
2/ type/multianswer/tests/upgradelibnewqe_test.php contains invalid expected value - see TODO
Tim Hunt