Author: Sam Hemelryk
MDL-29093 - Authentication improved new setting name and strings
http://git.moodle.org/gw?p=moodle.git;a=commit;h=6aa9352f668b736d21298c5d5acbe3651d6979f0
http://github.com/moodle/moodle/commit/6aa9352f668b736d21298c5d5acbe3651d6979f0
+ 2.1 en [authpreventaccountcreation,core_admin]
+ 2.1 en [authpreventaccountcreation_help,core_admin]
- 2.1 en [authonly,core_admin]
- 2.1 en [authonly_help,core_admin]