Assign contributor questionnaires per course type

[janno42]

Managers can assign questionnaires to all evaluations of a semester that are in preparation at once.
Currently, general questionnaires can be assigned by course type and contributor questionnaires can only be assigned to all contributors.

Instead, contributor questionnaires should also be assignable by course type. The form on the page should be divided into two columns: The first for "General questionnaires" and the second for "Contributor questionnaires". Each should have questionnaire selection fields for all course types, and for contributors the current field "All contributors" should also be displayed as the last input field.