code: func (h *Handler) serveEdgesTo(rw http.ResponseWriter, req *http.Request) {
  	defer httputil.RecoverJSON(rw, req)
  	var er EdgesRequest
  	er.fromHTTP(req)
  	res, err := h.EdgesTo(&er)
  	if err != nil {
  		httputil.ServeJSONError(rw, err)
  		return
  	}
  	httputil.ReturnJSON(rw, res)
  }
docs: // Unlike the index interface's EdgesTo method, the "edgesto" Handler
  // here additionally filters out since-deleted permanode edges.