finBatch and finBatchBank Business Layer objects; new script events added that run inside the database transaction

The current Pre and Post script events are outside the database transaction, so are of limited use.

The following new events have been added:

BatchCommitPreInTransaction
BatchCommitPostInTransaction
BatchBankCommitPreInTransaction
BatchBankCommitPostInTransaction

Note, this is noted as a breaking change because there is a small possibility that the existing "BatchCommitPre" script might behave different as the finBatch is now re-validated after the script has been run.