anchor.diff:  # R packages we need for devtools - and we need devtools to be able to update the rmarkdown package
   RUN DEBIAN_FRONTEND=noninteractive wget \
      http://mirrors.nics.utk.edu/cran/src/contrib/rstudioapi_0.5.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/withr_1.0.0.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/brew_1.0-6.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/roxygen2_5.0.1.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/rversions_1.0.2.tar.gz \
  
positive.code:    R6_2.1.2.tar.gz \
     curl_0.9.5.tar.gz \
     httr_1.1.0.tar.gz \
     rstudioapi_0.45.0.tar.gz \
     brew_1.0-6.tar.gz \
     roxygen2_5.0.1.tar.gz \
     XML_3.98-1.3.tar.gz \
  
negative.code:    R6_2.1.2.tar.gz \
     httr_1.1.0.tar.gz \
     rstudioapi_0.5.tar.gz \
     withr_1.0.0.tar.gz \
     brew_1.0-6.tar.gz \
     roxygen2_5.0.1.tar.gz \
     XML_3.98-1.3.tar.gz \
  