Commit the new CSV docs.

doc/d-utils.md

@@ -63,3 +63,9 @@ Parses given lines and returns list of lists of strings.
     (csv-parse fn . args)
 
 Uses ```csv-parse-lines``` on lines read from given file ```fn```.
+
+### csv-split-header [procedure]
+
+    (csv-split-header csv)
+
+Splits given loaded CSV into two tables at the first empty row.