Author: Andrew Davis
MDL-46035 mod_survey: a string change to make an error message always correct
http://git.moodle.org/gw?p=moodle.git;a=commit;h=f87c07303958fbac9290a5b99d0ba9725b1744c8
http://github.com/moodle/moodle/commit/f87c07303958fbac9290a5b99d0ba9725b1744c8
+ 2.6 en [guestsnotallowed,mod_survey]