anchor.diff:     bindrcpp_0.2.2.tar.gz \
      plogr_0.2.0.tar.gz \
      tidyselect_0.2.5.tar.gz \
  -   dplyr_0.8.0.1.tar.gz 
  +   dplyr_0.8.1.tar.gz 
   
   RUN DEBIAN_FRONTEND=noninteractive wget \
      https://archive.linux.duke.edu/cran/src/contrib/chron_2.3-53.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/data.table_1.12.0.tar.gz \
  +   https://archive.linux.duke.edu/cran/src/contrib/data.table_1.12.2.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/rematch_1.0.1.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/cellranger_1.1.0.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/tidyr_0.8.3.tar.gz \
  
positive.code:    https://archive.linux.duke.edu/cran/src/contrib/lazyeval_0.2.2.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/utf8_1.1.4.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/fansi_0.4.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/pillar_1.4.1.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/pkgconfig_2.0.2.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/tibble_2.1.3.tar.gz \
  
negative.code:    bindr_0.1.1.tar.gz \
     bindrcpp_0.2.2.tar.gz \
     tidyselect_0.2.5.tar.gz \
     dplyr_0.8.1.tar.gz 
  
  RUN rm \
     openintro_1.7.1.tar.gz \
  