Add variables to EventInfo for LHC train structure

For a BCID based correction we will require a few variables added to event info which use the LHC train structure to translate BCID into distance from the front of the train and the gap before the train such that we can determine if we are after an abort gap or after a long gap. For 8b4e as the tool treats all 8 bunch sets as a train we also store the situation 12 BCIDs before to see if we are in the first two sets of 8 bunches from a long gap.