Author: Pau Ferrer Ocaña
MDL-25979 signup: Usability message for recaptcha label form
http://git.moodle.org/gw?p=moodle.git;a=commit;h=3256b358cb3e96b23c5ef9e5140ea80bc331cee7
http://github.com/moodle/moodle/commit/3256b358cb3e96b23c5ef9e5140ea80bc331cee7
+ 2.9 en [security_question,core_auth]