added yet another test to verify logging behavior when logging errors
changed the order of operations when starting MSMQ transaction
made all saga persisters treat null the same way
updated changelog
Made AmbientTransactionContext aware of HttpContext and OperationContext instead of only using ThreadStatic context

Fixes bug when publishing and sending messages from a Web/WCF context
Throw exception if transaction is not started to avoid messages being dropped in the system dead letter queue
Fixed bug in WCF context wrapper
Disposing AmbientTransactionContext and IContext instances

To ensure TransactionContext is cleared on clear instead of when ASP.NET/WCF is clearing contexts
Reordered GetTransaction

To also check for state of MSMQ transaction in context - this is more important than to check for state of a new transaction
Reverting changes to AmbientTransactionContext and implemented hosting context management in TransactionContext - where it should be
Merge pull request #203 from jasperdk/master

TransactionContext [ThreadStatic] and ASP.NET is actually a problem
added some 'belt & suspenders' to ambient tx ctx
updated changelog
added necessary serialization ctors to exceptions
RebusBus.ToString and make SetNumberOfWorkers re-entrant
optimized data structure used by HeaderContext with hash code-based pre-lookup
added entry to changelog
added multi-threaded header context stress test and limited the number of buckets
made stress test parameterized and added test cases
ALT + ENTER