archiving old accounts

added account archiving in to redis persistance, so that unused accounts are not loaded anymore
This is an artefact too, at one point I meant to remove the accounts from memory, but this caused too many issues with the sync from slave bankers, so they are not removed from memory anymore, They simply get marked as closed, and the redis key gets moved from banker:accounts to banker:archive.
So on the next launch of the banker it will only reload the active accounts.