Add ellipsis

For r-lib/pillar#250.

Author: krlmlr

R/tbl_sum.R

@@ -3,7 +3,7 @@
 pillar::tbl_sum
 
 #' @export
-tbl_sum.tbl_df <- function(x) {
+tbl_sum.tbl_df <- function(x, ...) {
   c("A tibble" = dim_desc(x))
 }