Questionnaire install.xml and upgrade.php do not match

We (mrbriz and I at the OU) have just been through an exercise where we compared the current database tables in our database (the result of install.xml log ago, then upgrade.php since then) with the current definitions in install.xml.

We found issues in several plugins, including mod/questionniare. So, I have created this issue for the pull requests I am about to create.