add a filter to allow custom sales information to be added to purchase logs.  This custom information can come from
places like custom cart meta or custom sales meta, customer profiles or anywhere else
added wpsc_purchaselog_details_id()  as paramter to action at the suggest of @justinsainton
Merge pull request #823 from JeffPyeBrook/wpsc_additional_sales_item_info

Add a filter to allow custom information  on packing slips or other sales documents/displays