MDL-40056 events: Created Event classes to replace add_to_log() - mod_scorm

Created attempt_deleted event
Created interactions_viewed event
Created report_viewed event
Created sco_launched event
Created tracks_viewed event
Created user_report_viewed event
Created course module related events
MDL-40056 events: Add unit tests for new events
MDL-40056 events: Replace old add_to_log calls with new events