Author: Michael Aherne
MDL-36101 auth_shibboleth Show appropriate error message for suspended accounts
http://git.moodle.org/gw?p=moodle.git;a=commit;h=6dc38156a257a056edf2650f8478aaf431a7dd03
http://github.com/moodle/moodle/commit/6dc38156a257a056edf2650f8478aaf431a7dd03
+ 2.2 en [shib_invalid_account_error,auth_shibboleth]