OSIS-3461 Add AcademicCalendar migration files
OSIS-3461 Add AcademicCalendar migration files

uclouvain/OSIS-Louvain,uclouvain/OSIS-Louvain,uclouvain/osis,uclouvain/osis,uclouvain/OSIS-Louvain,uclouvain/osis,uclouvain/osis