gnu: Add r-proxy.

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

gnu: Add r-ggally.

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

gnu: Add r-progress.

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

gnu: Add r-reshape.

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

gnu: Add r-prettyunits.

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

gnu: Add r-ffbase.

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

gnu: Add r-ff.

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

gnu: Add r-fastmatch.

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

gnu: Add r-getoptlong.

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

gnu: Add r-dendextend.

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

gnu: Add r-compare.

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

gnu: Add r-png.

* gnu/packages/image.scm (r-png): New variable.

gnu: Add r-powerlaw.

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

gnu: Add r-circlize.

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

gnu: Add r-globaloptions.

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

gnu: Add r-shape.

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

gnu: Add r-calibrate.

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

gnu: Add r-auc.

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

gnu: Add r-annotationhub.

* gnu/packages/bioinformatics.scm (r-annotationhub): New variable.

gnu: Add r-interactivedisplaybase.

* gnu/packages/bioinformatics.scm (r-interactivedisplaybase): New variable.