eXist r18233
Write wrapper functions for group membership/management information because in recent versions of eXist, basic group information is a secret.
use sm:list-groups() instead of sm:get-groups() which is deprecated
use sm:remove-group() instead of deprecated sm:delete-group()
use sm:remove-group#1 instead of removed sm:delete-group#2. TODO: when sm:remove-group#2 is added, use it instead
Merge branch 'feature/upgrade-exist-user-group' into develop