Token auth: support lifetime types
Transaction chains, confirmations, resource locks

Transaction related changes were moved to a separate migration
that predates the storage migration.

Transactions now cannot exist just by themselves, but have to be
linked in a transaction chain, which groups them and gives them meaning.

Confirmations now support editing of attributes and tables
with composite primary keys.

Only vps create, start, stop and restart actions are operational, but only
without the storage migration, that will be implemented in later commits.

Gem composite_primary_keys was added to properly support composite
keys.