text: ## Run this script with:
  ## R CMD BATCH install-packages.r
  
  ## Create the personal library if it doesn't exist.
  ## Ignore a warning if the directory already exists.
  dir.create(Sys.getenv("R_LIBS_USER"), showWarnings=FALSE, recursive=TRUE)
  
  ## Install jsonlite and optparse packages
  install.packages(c("jsonlite", "optparse", "getopt"), Sys.getenv("R_LIBS_USER"), repos="http://cran.case.edu")