[Halld-physics] Cross Section plot update

[Thomas Britton]

As promised we looked into the plots from this morning;  in doing so a bug was discovered in phi's previous measurement parametrization function as well as the use of an outdated phi measurement.  The relevant new plots, as well as a second take on preliminary results to show at meson can be found here:
https://halldweb.jlab.org/DocDB/0036/003632/001/cross_section_updated_plots.pdf

Thanks for the comments,
Thomas