QPID-4327: Optimize brokertest.ready() to improve test runtimes.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1509418 13f79535-47bb-0310-9956-ffa450edef68
QPID-4327: Refactor to simplify TxAccept.

Removed un-necessary RangeOps layers.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1509419 13f79535-47bb-0310-9956-ffa450edef68
QPID-4327: Renamed ConfigurationObserver as BrokerObserver.

This class really was intended as a observer for broker-level events which
includes configuration but may in future include other non-configuration events
such as transactions.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1509420 13f79535-47bb-0310-9956-ffa450edef68
QPID-4327: Added TransactionObserver interface.

Added TransactionObserver interface, called at each point in a transaction's
lifecycle. Currently only a single observer can be associated with a
transaction.

Added startTx, startDtx to BrokerObserver so plugins can observe transactions
starting and set a TransactionObserver.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1509421 13f79535-47bb-0310-9956-ffa450edef68
QPID-4327: HA get rid of Primary::get() singleton.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1509422 13f79535-47bb-0310-9956-ffa450edef68