Shipment.

SHIPMENT UNDONE

Shipment and shipment rows have been rewritten.
The database tables no longer withhold useless data.
Shipment & warehouse core.

- Deliver shipment action completed.
- Warehouse_entry - warehouse_entry_spot link changes to many_to_many
Warehouse core.

- Purchase order should be finished.
- Supply should be finished.
- Sales order should be finished.
- Shipment layouts need to be fixed. Everything else seems fine.
Shipment & supply.

- Views finished.
- Warehouse entry type --> entry_type
Merge pull request #8 from harjis/joonas/shipment_2

Shipment and warehouse core.