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=19f2765be299cf377da839c28bf5b4c9de65e762
http://github.com/moodle/moodle/commit/19f2765be299cf377da839c28bf5b4c9de65e762
+ 2.8 en [guestsnotallowed,mod_survey]