Defined in tcl/ad-scope.tclif scope is not set in the topmost environment then public scope is assumed. if scope is group, it assumes group_vars_set is set in the topmost environment. returns appropriate scope admin footer. because it is only the programmers who can fix the pages, we should always use ad_footer. we mantain this as separate function for consistency and possible future changes in display, in which case this function may return something else than ad_footer