added most of ARM models from ch4-7
added congress model from ch7 and cleaned up other model directories
added grades simulation model from ch8
cleaned up more model directory files
added rest of ch9 models
added ch10 models
fixed sesame model
added ch12 models (sesame and radon)
removing old files
added R code using ggplot2 for most of ch3.1-3.6
added ch 3.7 code with new data files
added ARM files for Ch 2
added R code for Ch4.1-4.5
added R code for ARM Ch 4.6
added ARM Ch5.1 R code
added Ch5.2 of ARM
added ARM Ch5.4
added ARM Ch5.5
added most of Ch5 in ARM
fixed all of Ch5 ARM except 5.8