Including global track DCAs and global splitting for MCH halves

Included two new sets of histograms to take advantage of scaled MFT tracks and comparing them with their MCH counterpart, if matched.
- DCAs for the global tracks, DCA trends as a function of collision z and DCA subtracted histograms (scaled MFT - MCH).
- [WIP] Further distinction in mu+ and mu- for the top and bottom halves of the global tracks (using scaled MFT). These histograms already existed for the standalone MCH case.

Author: ppoava