The routines in this file enables you to:
. Add a member to a group.
. Get data of a group.
. Get the tag of the group to which the specified input tag belongs.
. Create a group from a set of group members.
. Delete a member from a group.
. Remove all members of a group, delete the group, and ungroup the immediate
group and all subgroups.
. Remove all members of a group, delete the group, ungroup only the immediate
group, and allow subgroups to remain.