GF: Introduce tooltips for the form and field settings
Make this plugin a network-only plugin
Network: redefine how network settings are processed and updated
Use site options for plugin settings in BuddyPress extension
Use more site options in plugin settings
Shorten logic for using BP Group Hierarchy

Introduces a new `VGSR_BuddyPress::get_group_hierarchy()` method to return
the child groups of the given group id(s).

Also we now use `groups_get_groups()` to determine group membership
instead of multiple uses of `group_is_user_member()`.
Update docblock of `VGSR_BuddyPress:user_in_group()`