Author: Paul Holden
MDL-72499 event: add/correct event language strings as required.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=55deada25aa6b3f526178717729e571765a6f538
http://github.com/moodle/moodle/commit/55deada25aa6b3f526178717729e571765a6f538
+ 3.10 en [eventhighscoreadded,mod_lesson]
+ 3.10 en [eventhighscoresviewed,mod_lesson]