Author: Paul Holden
MDL-84017 ai: help icons to describe the usage report token columns.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=3eceaf5388c638b3f253bca949b6cea860b72d7a
http://github.com/moodle/moodle/commit/3eceaf5388c638b3f253bca949b6cea860b72d7a
+ 5.0 en [completiontokens_help,core_ai]
+ 5.0 en [prompttokens_help,core_ai]