Author: Mark Nelson
MDL-60969 auth_ldap: replace hardcoded strings in config settings
http://git.moodle.org/gw?p=moodle.git;a=commit;h=7a06e15952417b0749f2e0a530f9e07efd5232d7
http://github.com/moodle/moodle/commit/7a06e15952417b0749f2e0a530f9e07efd5232d7
+ 3.4 en [auth_ldap_expiration_desc,auth_ldap]