MDL-11419 - groups: interface enhancements + new features:

MDL-11419 - groups: interface enhancements + new features:

    * Display the grouping a course module belongs to on the course page - for course managers only.
    * When adding users to groups, display the groups a user already belongs to.
    * Added an overview report that shows groupings, groups and members for a course.
    * Added a dialogue to automatically create groups and assign members based on either the number of desired groups or the number of desired users per group.