New features included in this new version:

• Added support for background color
• It is now possible to override the default style for the spreadsheet. This leads to a big perf improvement.
• Empty cells can now have a custom style applied to them

Fixes:

• Fix for borders support in Excel 2013+
• Cells formatted as dates for XLSX files should respect the shouldFormatDate option
• Extended support for prefixed XML files
• A few other minor/perf changes