CONN-335: adding TransactionStore interface and implementations.
CONN-335: all TransactionStore impls return null when no transactionId is found.
CONN-335: introducing TransactionStore proxy.
CONN-599: fix for using transaction id instead of relatesto id for event logging.
CONN-335: updates to soapui test.
CONN-335: updating regression to test assuming CONN-601 bug.
Merge pull request #571 from msweaver/CONN-335

Conn 335