Refactor Session construction in test code

Currently to create some of the Session related test cases it is necessary to use constructs like this:

Session session = new Session(new UnitTestApplication(), new MemoryStoreFactory(),
sessionID, null, null, new ScreenLogFactory(true, true, true),
new DefaultMessageFactory(), isInitiator ? 30 : 0, false, 30, true, resetOnLogon,
false, false, false, false, false, true, false, 1.5, null, validateSequenceNumbers,
new int[]

{ 5 }

, false, disconnectOnError, false, true, false, true, false, null,
true, 0, false, false);

This kind of code turns from an asset into a liability pretty quickly, so the sooner it is rationalised the better. The Session constructor itself isn't very pretty either with its 30+ parameters.