MDL-40063 mod_quiz: replaced 'delete override' add_to_log call with events
MDL-40063 mod_quiz: replaced 'continue attempt' add_to_log call with an event
MDL-40063 mod_quiz: replaced 'preview' add_to_log call with an event
MDL-40063 mod_quiz: replaced 'attempt' add_to_log call with an event
MDL-40063 mod_quiz: replaced ‘manualgrade’ add_to_log call with an event
MDL-40063 mod_quiz: created 'override_created' events