feat: reimagine certificate display settings The course settings `certificate_available_date` (CAD) and `certificates_display_behavior` (CDB) were previously acting indedependantly of one another. They now work in tandem. This change: - limits CDB to a dropdown - removes "early_with_info" and adds "end_with_date" - only takes CAD into account if "end_with_date" is selected - Moves CDB to the main course schedule settings page - updates CourseOverview model and CourseDetails objects to validate these fields and choose sane defaults if they aren't expected values This work was previously done in bd9e7dd (complete with bugs), so this version is toggleable via the ENABLE_V2_CERT_DISPLAY_SETTINGS setting
Open edX -------- This is the root package for Open edX. The intent is that all importable code from Open edX will eventually live here, including the code in the lms, cms, and common directories. If you're adding a new Django app, place it in core/djangoapps. If you're adding utilities that require Django, place them in core/djangolib. If you're adding code that defines no Django models or views of its own but is widely useful, put it in core/lib. Note: All new code should be created in this package, and the legacy code will be moved here gradually. For now the code is not structured like this, and hence legacy code will continue to live in a number of different packages.