Add tests for Turbo MC processing
This is a start in fixing LHCBPS-1771. It runs DaVinci over 2015 and 2016 DST MC and 2016 microDST MC.
What I'd also like to test is that the truth-level branches of the ntuple are filled correctly, i.e. that the truth-matching is working. I'm not sure if it's best to try and integrate this into the tests already in this MR, or add separate tests that check the output files.