Instead of let the ltid in the master app module, the transaction manager keep it and compute the next each time a transaction begins.
The getNextTID() method has moved from util to transactions module.
Last TID collected during recovery is also handled by the transaction manager through setLastTID() method.
Any reference to app.ltid are updated,

git-svn-id: https://svn.erp5.org/repos/neo/trunk@1455 71dcc9de-d417-0410-9af5-da40c76e7ee4