SalesOrderShipment (#697)

* Add detail widget for SalesOrderShipment

* Support editing of shipment details

* Rearrange SalesOrderDetail page

* Add support for attachments against shipment model

* refactoring

* Add shipment details page

* Add user actions for shipments:

- Check / uncheck
- Take photo

* Placeholder action to send shipment

* Send shipment from app

* Display pending shipments on the home screen

* Improve rending for shipments list

* Add class definition for SalesOrderAllocation

* Display list of items allocated against SalesOrderShipment

* Bump release notse

* Click through to stock item

* Bump version number

* dart format

* cleanup

* Remove unused imports

lib/widget/order/so_line_detail.dart

@@ -244,7 +244,7 @@ class _SOLineDetailWidgetState extends RefreshableState<SoLineDetailWidget> {
     }
 
     // External link
-    if (widget.item.link.isNotEmpty) {
+    if (widget.item.hasLink) {
       tiles.add(
         ListTile(
           title: Text(L10().link),