Author: Paul Holden
MDL-84901 auth: specific session start error language string.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=6462abc6df5748740308f13a0ecf5209b8f919a0
http://github.com/moodle/moodle/commit/6462abc6df5748740308f13a0ecf5209b8f919a0
+ 4.5 en [sessionstarterror,core_error]