Refactor the 'precedence' package and add the latest ATLAS MC data...

Refactor the 'precedence' package and add the latest ATLAS MC data reconstruction scenario to the Gaudi Hive portfolio of simulators

This merge request contains refactoring of the 'precedence' package (used for configuration of Hive execution flow simulations), which makes it experiment independent. Also, it adds the latest ATLAS MC data reconstruction scenario to portfolio of Hive execution flow simulators.

See merge request !204