This patch provides functionality to allow the
assign activity to have timed attempts for submissions.
It includes the logic, UI and adminstration changes
fot timed submissions.
This class would belong more appropriately within the 'user' API
(core_user) instead of within the 'core' API, since it is
directly related to user data.
Since the class has only just been added to Moodle, now is a good
time to move it.
In all cases changes have been kept to a minimum while not making
the code completely horrible. For example, there are many instances
where it would probably be better to rewrite a query entirely, but
I have not done that (in order to reduce the risk of changes).
Fixed a bug in which $fromform->sortorder wasn't set before passing
$formdata to assign_update_events, resulting in the existing event
priority being incorrectly nulled and breaking the effective override.
* Fix the parameters being passed for the assign constructor.
* Use assign::get_instance() instead of assign::get_context() to fetch
the assignment instance's properties.
