Parsing Command-Line Arguments and Simple Variable Interpolation
rjson, GlobalOptions (>= 0.1.0), methods, crayon
testthat (>= 1.0.0), knitr, markdown, rmarkdown
This is a command-line argument parser which wraps the 
    powerful Perl module Getopt::Long and with some adaptations for easier use
	in R. It also provides a simple way for variable interpolation in R.