Notification of string changes

Author: David Mudrák
MDL-58692 auth: Improve the migration of auth setting names
Some auth plugins used to have a mix of the legacy style of plugin names
in config_plugins table (such as 'auth/mnet') and the new correct
style (such as 'auth_mnet'). Attempting to rename the setting plugin via
low level SQL UPDATE could lead to duplicate key violation.

The patch introduces a new helper function to safely migrate the old
settings to the new ones, eventually informing the admin about the
values mismatch.


http://git.moodle.org/gw?p=moodle.git;a=commit;h=31bd1023166bfd284ff0b69df58714b734c973be
http://github.com/moodle/moodle/commit/31bd1023166bfd284ff0b69df58714b734c973be

+ 3.3 en [settingmigrationmismatch,core_auth]