anchor.diff:  RUN DEBIAN_FRONTEND=noninteractive apt-get install -y \
      gdebi-core \
      libapparmor1
  -RUN DEBIAN_FRONTEND=noninteractive wget https://s3.amazonaws.com/rstudio-dailybuilds/rstudio-server-0.99.681-amd64.deb
  -RUN DEBIAN_FRONTEND=noninteractive gdebi -n rstudio-server-0.99.681-amd64.deb
  -RUN rm rstudio-server-0.99.681-amd64.deb
  +RUN DEBIAN_FRONTEND=noninteractive wget https://download2.rstudio.org/rstudio-server-0.99.902-amd64.deb
  +RUN DEBIAN_FRONTEND=noninteractive gdebi -n rstudio-server-0.99.902-amd64.deb
  +RUN rm rstudio-server-0.99.902-amd64.deb
   
   # update the R packages we will need for knitr
   RUN DEBIAN_FRONTEND=noninteractive wget \
  -   http://mirrors.nics.utk.edu/cran/src/contrib/knitr_1.12.3.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/knitr_1.13.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/yaml_2.1.13.tar.gz \
  -   http://mirrors.nics.utk.edu/cran/src/contrib/htmltools_0.3.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/Rcpp_0.12.5.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/htmltools_0.3.5.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/caTools_1.17.1.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/bitops_1.0-6.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/digest_0.6.9.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/stringr_1.0.0.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/markdown_0.7.7.tar.gz \
  -   http://mirrors.nics.utk.edu/cran/src/contrib/highr_0.5.1.tar.gz \
  -   http://mirrors.nics.utk.edu/cran/src/contrib/formatR_1.2.1.tar.gz \
  -   http://mirrors.nics.utk.edu/cran/src/contrib/evaluate_0.8.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/highr_0.6.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/formatR_1.4.tar.gz \
  +   http://mirrors.nics.utk.edu/cran/src/contrib/evaluate_0.9.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/mime_0.4.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/stringi_1.0-1.tar.gz \
      http://mirrors.nics.utk.edu/cran/src/contrib/magrittr_1.5.tar.gz
  
positive.code:    chron_2.3-47.tar.gz \
     data.table_1.9.6.tar.gz \
     cellranger_1.0.0.tar.gz \
     tidyr_0.4.0.tar.gz \
     googlesheets_0.1.0.tar.gz \
     readr_0.2.2.tar.gz \
     selectr_0.2-3.tar.gz \
     rvest_0.3.1.tar.gz \
     pbkrtest_0.4-6.tar.gz 
  
negative.code:    bitops_1.0-6.tar.gz \
     caTools_1.17.1.tar.gz \
     digest_0.6.9.tar.gz \
     Rcpp_0.12.5.tar.gz \
     htmltools_0.3.5.tar.gz \
     yaml_2.1.13.tar.gz \
     stringi_1.0-1.tar.gz \
     magrittr_1.5.tar.gz \
     mime_0.4.tar.gz \
     stringr_1.0.0.tar.gz \
     highr_0.6.tar.gz \
     formatR_1.4.tar.gz \
     evaluate_0.9.tar.gz \
     markdown_0.7.7.tar.gz \
     knitr_1.13.tar.gz 
  
  RUN rm \
     evaluate_0.9.tar.gz \
     formatR_1.4.tar.gz \
     highr_0.6.tar.gz \
     markdown_0.7.7.tar.gz \
     stringi_1.0-1.tar.gz \
     magrittr_1.5.tar.gz \
     stringr_1.0.0.tar.gz \
     knitr_1.13.tar.gz \
     yaml_2.1.13.tar.gz \
     Rcpp_0.12.5.tar.gz \
     htmltools_0.3.5.tar.gz \
     caTools_1.17.1.tar.gz \
     bitops_1.0-6.tar.gz \
     digest_0.6.9.tar.gz \
  