Recipe to turn davinci run-mc options, etc., into gaudirun.py options

Follow-up from discussion at !599 (comment 5069308).

The recipe for turning the davinci run-mc options into gaudirun.py options is reported in the DaVinci documentation at https://lhcb-dpa.web.cern.ch/lhcb-dpa/wp3/index.html#how-to-run-davinci-with-gaudirun-py.
Two example of the same option file valid for the davinci run-mc and gaudirun.py are available in DaVinciExamples packages, namely test_davinci_tupling_from_hlt2.qmt and test_davinci_tupling_from_hlt2_gaudirun.qmt, respectively.