Allow no colnames with PDF output when booktabs enabled
diff --git a/DESCRIPTION b/DESCRIPTION
index f4eab25..8d7bbdd 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -31,6 +31,7 @@
 Imports:
     knitr (>= 1.16),
     magrittr,
+    stringi,
     stringr (>= 1.0),
     xml2,
     rvest,