Author: Andrew Robert Nicols
MDL-32142 Add missing langstring for section backups
http://git.moodle.org/gw?p=moodle.git;a=commit;h=8d1f38638560291b8e80f9b656b81906dc6184cd
http://github.com/moodle/moodle/commit/8d1f38638560291b8e80f9b656b81906dc6184cd
+ 2.3 en [backuptypesection,core_backup]