All compute nodes are public now

source_administration is not used anymore on Compute Node

slapos_subscription_request: hardcode automated ledger category for the newly created sale packing list

slapos_subscription_request: hardcode automated ledger category for the newly created accounting transactions

XXX TODO check if some are missing

XXX TODO fix broken TALES expression which prevent entering invaludated/suspended

XXX FOrces tests to fail as much as possible if ledger is not configured.
Add test to ensure constraint is configured