Add new 'Rbs_Commerce_Carts_Cleanup' job
Update order editor:
 - the order is now editable only if the processingStatus is "edition"
 - add buttons to switch between "edition" and "processing" statuses
 - homogenize line adding
 - don't use a document list for lines (they are not documents) but use the same markup
 - show discounts and fees in total
 - some other fixes and visual enhancements
Add coupon, discounts and fees edition in orders.