Updating DigitizationAlg and PileUpToolsAlg to use private ToolHandles
This commit updates DigitizationAlg and PileUpToolsAlg to use
a private ToolHandleArray<IPileUpTool>. This will change the name
of the PileUpTools from ToolSvc.PileUpToolGivenName to
AlgorithmName.PileUpToolGivenName.
Because the PileUpTool names changed then the test_MC16a_Digi_tf_configuration
unit test had to be updated accordingly.
Edited by John Derek Chapman