[UPDATED] Export/Import module for Opencart 1.3.1

The Export/Import module has been updated to work with OpenCart 1.3.1. I haven't been able to upload it to the Opencart's contributions section. Until this has been sorted out, you can download it from
http://www.mhccorp.com/downloads-opencart.shtml

Previous releases of the Export/Import won't work with the new OpenCart 1.3.1.

A new column has been added in the spreadsheet for the 'measurement unit'.