make location repeatable

Currently location is a single sub-object field in poLine. In order to support an order line which spans multiple locations, we need to make this repeatable (an array of location sub-objects).

Involves work in acq-models, as well as the mod-orders code. The main changes in the business logic:

• Validation
  • locations should be required depending on order_format (see MODORDERS-117 for details)
  • physical/electronic quantity should depend on PO Line's order_format (see MODORDERS-117 for details)
  • sum of physical quantity of all locations must not exceed cost.quantity_physical
  • sum of electronic quantity of all locations must not exceed cost.quantity_electronic
• Inventory
  • One Holding should be created (if not yet exists) per each location
  • Items should be created (if not yet exists) per each location depending on physical and/or electronic quantity

Acceptance Criteria:

• the schemas and examples are updated
  • composite_po_line
  • po_line
  • composite_purchase_order (examples)
  • composite_po_line_collection (examples)
  • po_lines_collection (examples)
• mod-orders code is updated
  • only valid combination of order_format and physical/electronic quantity of cost and locations objects results to success processing, otherwise 400 (Bad Request) with error is returned
  • In case Inventory interaction required, a holding is created per location and corresponding amount of items linked to holding
• unit tests are updated
• api tests are updated

Affected modules:

• mod-gobi
• ui-orders
• mod-orders-storage