New MC-based JMS calibration
This MR is the implementation of the JMS calibration step for the new version of JetCalibTools as discussed at the JSV hackathon last week.
The RootHelper code is a simple copy of the files in JetCalibTools. Once the new version of JetCalibTools has been fully validated, the current files in JetCalibTools will be deleted and only the ones in JetToolHelpers will be kept.
The new version has been validated by comparing to the current implementation and no differences larger above 1 MeV were observed on a test sample of approx. 5k events. A larger scale validation together with all other steps will follow. The code uploaded here will not be used before that big validation.