Now Auth plugins can register auth_validate_form to get a chance
to validate config form input. Needed on MOODLE_16_STABLE to fix
a bug with auth/db.
The auth API must follow suit with the enrol API, where we can safely
do method_exists().
pluggable modules in the 'auth' directory.
Everything is done through authentication_user_login in lib/moodlelib.php
As well as the old default "email" confirmation, I added a new type of
confirmation "none", which basically does no confirmation at all.
martinlanghoff