Empact/roo — pull request #23 by airblade (2013-03-15 15:45:54+00:00)
Title: Discard empty rows before reading them.

This can massively speed up the reading of an xlsx spreadsheet. It was
motivated by trying to read a spreadsheet with 900 rows of content and
900,000 empty rows. Before this change it took tens of minutes or
longer; after the change it took a few seconds.