Space push

/by apr/ As of r2541 we have a new Space operation, Space.push. Space.push is similar to Space.out but places the entry at the head of the list. I tried hard to avoid adding new operations to the Space in order to keep it simple but The Gladiators Team found an extremely interesting use case for it. Under heavy load, when a transaction gets resumed, it competes with new incoming transactions in order to get its CPU slot, but this transaction has already competed once (at the beginning) and it's unfair to have it on queue again. With the new Space.push operation (implemented in r2541) and changes to the TransactionManager (implemented in r2542) a resumed transaction would get priority over a new one. jPOS-EE has been updated with a binary version of r2542.