MDL-42400 generator: module generators call add_moduleinfo instead of direct inserts
MDL-42400 generator: save db query in module generation
MDL-42400 modlib: speed up add_moduleinfo, remove unnecessary queries

removed code that was causing unnecessary DB queries, this significantly speeds up data generators
MDL-42400 mod_glossary: data generator for glossary
MDL-42400 mod_lesson: data generator for lesson
MDL-42400 mod_survey: data generator for survey
MDL-42400 mod_url: data generator for url
MDL-42400 mod_wiki: data generator for wiki
MDL-42400 mod_workshop: data generator for workshop
MDL-42400 mod_scorm: data generator for scorm
generators for imscp (unfinished)