Grades cleanup: remove read_only param and create method

common/djangoapps/student/views.py

lms/djangoapps/ccx/tests/test_field_override_performance.py

lms/djangoapps/ccx/tests/test_views.py

lms/djangoapps/ccx/utils.py

lms/djangoapps/ccx/views.py

...ps/certificates/management/commands/fix_ungraded_certs.py

lms/djangoapps/certificates/queue.py

lms/djangoapps/certificates/tests/test_queue.py

lms/djangoapps/courseware/tests/test_submitting_problems.py

lms/djangoapps/courseware/tests/test_views.py

lms/djangoapps/courseware/views/index.py

lms/djangoapps/courseware/views/views.py

lms/djangoapps/gating/tests/test_integration.py

lms/djangoapps/grades/api/tests/test_views.py

lms/djangoapps/grades/api/views.py

lms/djangoapps/grades/config/__init__.py

lms/djangoapps/grades/course_data.py

lms/djangoapps/grades/course_grade.py

lms/djangoapps/grades/course_grade_factory.py

lms/djangoapps/grades/signals/handlers.py