In order to do this in a sane way, I cleaned up a lot of old mess,
inclduing:
1. Previously, qtype_calcuated used ->answeres when importing, and
->answer when saving the form. This was crazy, so I fixed it, and
stripped out the code that made the alternative variable name work.
2. Similarly, it could handle ->answer being either an array, such as
you would get form the HTML editor, or a simple string, which is what
you get form the form. I simplified that too.
3. Finally, I made import use a transaction around saving each
question, so we don't get half questions in the database when an error
occurs.
Tim Hunt
94ac7a87fa