Add export functionality to course book

The contents of a course book should be exportable, e.g. in PDF format. It should be configurable which filters should be applied when exporting, e.g. the school term that should be covered or the groups/courses the export should contain.

• Use existing view for PDF generation and use new data model

• Move different parts into own templates

• Button in coursebook "Print"

  • opens dialog allowing to configure the printout
    • which groups to include (default: currently selected in the coursebook)
    • which parts to include (default: site preference)

• just use days instead of weeks in coursebook table

• introduce a second PDF export view for a single detailed overview of a person

• use separate lists for participation status and personal notes on detail overview of person

• respect permissions for personal details about persons (maybe already the case)

Configurable parts (each in own templates):

1. cover sheet (mandatory)
2. short names
3. persons table
4. teachers and subjects table (timebound course configs if lesrooster is used)
5. detail overviews of persons
6. actual coursebook

base on !396 (merged) and !361 (merged)