TDR code, aka code that would break master but is needed to run TDR tests

The breaking is mainly in the MC linking. This code needs some merge requests from Gaudi to be included, namely gaudi/Gaudi!536 (merged), gaudi/Gaudi!537 (merged) and gaudi/Gaudi!538 (merged) Note that the set of commits in this merge request should be reviewed before merging, even if the MC linking issue if solved. Some of the code may not be production ready