Initialize exam session
In the all results page, there should be button for initialize exam session that will lead us to a page with:
- selection of exam session
- button for creation of the results for that session.
When the button is clicked, we create an empty Results (result without pdf) entity for all course groups (courses x professors pairs) in selected exam session.
Make sure that this exam session is not initialized previously. (this is additional requirement. Initially without this check)