Sales Order - ability to manually update despatch date (6-1765)

[steveblamey]

When creating a sales invoice from a sales order, the invoice despatch date and invoice date is taken from the latest order line despatch date. This is either set as "today's" date, for picked lines, or set by the despatch module when the goods are despatched.

For picked lines only, there needs to be a to update the order line with the actual despatch date. This will allow for manual despatch where invoicing occurs at a later date; the invoice date needs to be the actual date of despatch and not the date the invoice was created.