Update 04.12.2019 -- Run 9 pp: Still More (and Better) Track Comparisons Between Pythia6 and Pythia8

[Recorded on 05.14.2019] This is a re-do of the comparisons here:

https://drupal.star.bnl.gov/STAR/blog/dmawxc/update-04042019-run-9-pp-pythia6-and-pythia8-particle-vs-detector-level-different-trigge

In the above comparisons, I wasn't calculating the detector-level delta-phi correctly for the Pythia6 detector-level and I wasn't matching detector-to-particle-level in the Pythia6 cases. These have been fixed below.