gnu: r-lambda-r: Update to 1.2.

* gnu/packages/statistics.scm (r-lambda-r): Update to 1.2.

gnu: r-gridextra: Update to 2.3.

* gnu/packages/statistics.scm (r-gridextra): Update to 2.3.

gnu: r-dplyr: Update to 0.7.3.

* gnu/packages/statistics.scm (r-dplyr): Update to 0.7.3.

gnu: r-crayon: Update to 1.3.4.

* gnu/packages/statistics.scm (r-crayon): Update to 1.3.4.

gnu: r-svglite: Update to 1.2.1.

* gnu/packages/statistics.scm (r-svglite): Update to 1.2.1.

gnu: r-mgcv: Update to 1.8-21.

* gnu/packages/statistics.scm (r-mgcv): Update to 1.8-21.

substitute: Close the download port after substitution finished.

* guix/scripts/substitute.scm (progress-substitution): Call 'close-port'
after 'restore-file'.

gnu: r-rcas: Update to 1.3.4.

* gnu/packages/bioinformatics.scm (r-rcas): Update to 1.3.4.

gnu: r-caret: Update to 6.0-77.

* gnu/packages/statistics.scm (r-caret): Update to 6.0-77.
[propagated-inputs]: Remove r-car; add r-recipes and r-withr.

gnu: r-rstudioapi: Update to 0.7.

* gnu/packages/statistics.scm (r-rstudioapi): Update to 0.7.

gnu: r-openssl: Update to 0.9.7.

* gnu/packages/statistics.scm (r-openssl): Update to 0.9.7.
[inputs]: Replace openssl with libressl.

gnu: Add r-recipes.

* gnu/packages/cran.scm (r-recipes): New variable.

gnu: Add r-ipred.

* gnu/packages/cran.scm (r-ipred): New variable.

gnu: Add r-rcpproll.

* gnu/packages/cran.scm (r-rcpproll): New variable.

gnu: Add r-gower.

* gnu/packages/cran.scm (r-gower): New variable.

gnu: Add r-ddalpha.

* gnu/packages/cran.scm (r-ddalpha): New variable.

gnu: Add r-timedate.

* gnu/packages/cran.scm (r-timedate): New variable.

gnu: Add r-dimred.

* gnu/packages/cran.scm (r-dimred): New variable.

gnu: Add r-prodlim.

* gnu/packages/cran.scm (r-prodlim): New variable.

gnu: Add r-drr.

* gnu/packages/cran.scm (r-drr): New variable.