Author: Dan Poltawski
MDL-36109 accesibility: use proper words for logo alt text
http://git.moodle.org/gw?p=moodle.git;a=commit;h=3e443eb1f3aae1c6ab430b05a6779e15d7f1f14f
http://github.com/moodle/moodle/commit/3e443eb1f3aae1c6ab430b05a6779e15d7f1f14f
+ 2.9 en [moodlelogo,core]