Merge pull request #6730 from OmarIthawi/edraak/unicode-fixes-log-username

...on/djangoapps/student/management/commands/assigngroups.py

common/djangoapps/student/models.py

common/djangoapps/student/views.py

lms/djangoapps/certificates/views.py

lms/djangoapps/courseware/grades.py

...ngoapps/courseware/management/commands/regrade_partial.py

...apps/courseware/management/commands/remove_input_state.py

lms/djangoapps/instructor/tests/test_api.py

lms/djangoapps/instructor/views/api.py

lms/djangoapps/instructor/views/legacy.py

lms/djangoapps/lms_migration/migrate.py

lms/djangoapps/shoppingcart/models.py

lms/djangoapps/shoppingcart/tests/test_views.py

lms/djangoapps/shoppingcart/views.py

lms/djangoapps/verify_student/views.py