ldb: Ensure to decrement the transaction_active whenever we delete a transaction

ldb: Ensure to decrement the transaction_active whenever we delete a transaction

This is in the error path for prepare_commit, which rarely fails, but
when it does we need to ensure that when a new transaction is opened,
that it really starts a new transaction.

We bump the version to recognise critical fix for the AD DC

Without this fix, a single invalid inbound replicated link disables
all subsequent replication as we operate without a transaction (which
is refused by ldb_tdb).

Andrew Bartlett

Reviewed-by: Matthieu Patou <mat@matws.net>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
(cherry picked from commit 1d1ea72574cfa22ee6207d0e9787d0271db3b5c2)

The last 13 patches address bug #9609 - backport tdb/ldb changes.

Autobuild-User(v4-0-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-0-test): Mon Jan 28 12:50:56 CET 2013 on sn-devel-104