This patch includes following changes and new features:
* Group sync in enrol_cohort plugin.
* Option for editing of role in existing cohort sync instance.
* Group memberships are now restored after enrolments.
* New enrol method for restore of protected group membership.
* New component callback 'restore_group_member' for restore of general plugin group membership.
* New component callback 'restore_role_assignment' for restore of general plugin role assignments.
* Implemented group membership protection in enrolment UI.
* Other minor fixes and cleanup.
Notes:
* The YUI base enrolment page is not reimplemented yet - see MDL-35618.
Includes option to convert all enrolments to enrol_manual instances, support for mapping of custom fields and fixes for several other problems. This does not include support for custom enrol tables, it will be addressed in another issue.
Some early steps in restore are using capability checks to decide how to
restore some information. But at that stage, if the course contents have
been removed and the user had perms at course level only (usually teacher)
the process can fail because some content is not restoreable due to the
lack of permissions.
Moving the restorer step to the beginning really helps is those situations
and it does not hurt at all.
Also, fixed one notice detected when testing this.
* Category + course selectors now perform required capability checks
* Show/Hide settings from UI tested and implemented for overwrite_conf setting
* Final continue button is GET rather than post
* Temp zip file is deleted after successfull extraction
* Removed previous button from settings stage MDL-23480
