[FIX] stock: partial deliveries switch on delivered picking

Users don't care for the backorder picking precisely because they can't process it, whereas they may have to do some more things on the picking they processed: invoice it, print delivery orders or transportation stickers..
Refresh the browse record after changing the name to avoid the need to rebrowse.
Fixes #1372
Merge branch '7.0' of https://github.com/odoo/odoo into 7.0-linux64