Update 02.26.2018 -- Average Trigger Et

To make sure we're comparing apples-to-apples when comparing our pp (and Pythia) results to our AuAu results, I've plotted the trigger Et distributions for both pi0 and gamma-rich triggers in data and pythia.  The average of each distribution is quoted on the plots.  Note that I have not removed bad runs and hot towers from the data distribution.  However, the impact here should be small if not negligible.