Different finish dates for different groups #359
Description
Describe the feature
The college and AI360 have different start/end dates for the semesters. So, they need to get different amount of sport hours, and they don't have separate summer trimester.
Suggested solution
Maybe we can create different Semester entities for them.
Maybe the trainings should not be linked to Semester (so they exist during holidays too), and different groups have different dates for semesters.
As a quick solution: we may just specify multiple semester end dates for each such group.
Additional context
May be solved together with #336