Updates to Operations.R, RunJAGS.R, make.SS.plots.R, run.SS.model.R.  Created new file, get.site.data.R.

Changed Operations.R to include a data download/update step. 
Created file/function get.site.data.R to perform that data download/update.
Fixed bugs in RunJAGS.R that prevented run.SS.model.R from running in function call form.
Changed make.SS.plots.R to plot GCC and MODIS data on same plot.