improvements to switch to vectors over c-style arrays

Created by: marc1uk

Fixes the bug with the tCorrected array, which would be sorted over it's full 500 element range, but that range was never initialized. This would read arbitrary uninitialized memory space, and would also sort in digits from previous events if there were fewer digits in subsequent events (as these elements would not be over-written).

Also contains new histograms to observe vertex error and 'isANNIE' switches to allow tanks with y as the cylinder axis, and uses WCSimRootGeom::GetWCOffset() to account for tanks that are not centred on the origin.

Constants and detector-specific functions were pulled to an anonymous namespace at the start of the script to make their presence and values clear.

Finally some minor modifications were needed to allow compilation with ROOT6.