gnu: python-semver: Fix build.

* gnu/packages/python-xyz.scm: Add python-appdirs, python-distlib,
  python-importlib-metadata, python-filelock, and python-six to native-inputs
  in order to run the test suite.

gnu: Fix build of python-velocyto.

* gnu/packages/bioinformatics.scm (python-velocyto): Add python-joblib to
  native-inputs to make the test suite run succesfully.

gnu: Add vim-asyncrun.

* gnu/packages/vim.scm (vim-asyncrun): New variable.

gnu: Add nyancat.

* gnu/packages/toys.scm (nyancat): New variable.

gnu: Update python-statsmodels to 0.11.1.

* gnu/packages/statistics.scm (python-statsmodels): Update to 0.11.1.

gnu: Add sycamore.

* gnu/packages/lisp-xyz.scm (cl-sycamore, sbcl-sycamore): New variables.

gnu: emacs-sly: Update to 20200228.

* gnu/packages/emacs-xyz.scm (emacs-sly): Update to 20200228.

gnu: r-desolve: Update to 1.28.

* gnu/packages/cran.scm (r-desolve): Update to 1.28.

gnu: r-umap: Update to 0.2.5.0.

* gnu/packages/cran.scm (r-umap): Update to 0.2.5.0.
[native-inputs]: Add r-knitr.

gnu: r-rcppannoy: Update to 0.0.16.

* gnu/packages/cran.scm (r-rcppannoy): Update to 0.0.16.
[native-inputs]: Remove r-knitr.

gnu: r-quantmod: Update to 0.4-16.

* gnu/packages/cran.scm (r-quantmod): Update to 0.4-16.

gnu: r-vcd: Update to 1.4-6.

* gnu/packages/cran.scm (r-vcd): Update to 1.4-6.

gnu: r-ggrepel: Update to 0.8.2.

* gnu/packages/cran.scm (r-ggrepel): Update to 0.8.2.

services: cuirass: Allow passing extra command line options.

This is so that the options supported by the service configuration don't have
to always be changed. Generally though all options should be explicitly
supported and documented, so this is mostly to facilitate experimentation.

* gnu/services/cuirass.scm (<cuirass-configuration>): Add an extra-options
field.
(cuirass-shepherd-service): Pass the extra options to the shepherd servvices.
* doc/guix.texi (Continuous Integration): Document it.

services: guix-data-service: Allow passing extra options.

This is so that the options supported by the service configuration don't have
to always be changed. Generally though all options should be explicitly
supported and documented, so this is mostly to facilitate experimentation.

* gnu/services/guix.scm (<guix-data-service-configuration>): Add extra-options
and extra-process-jobs-options to the record type.
(guix-data-service-shepherd-services): Handle these new configuration record
fields.
* doc/guix.texi (Guix Data Service): Document these new options.

gnu: guix-data-service: Update to 0.0.1-18.18eb9df.

* gnu/packages/web.scm (guix-data-service): Update to 0.0.1-18.18eb9df.
(inputs, native-inputs): Switch to using the Guile 3 package variants where
applicable.

gnu: python-virtualenv: Update to 20.0.8.

* gnu/packages/python-xyz.scm (python-virtualenv): Update to 20.0.8.
  [arguments]: Remove the now-redundant 'disable-failing-test phase.
  [native-inputs]: Add python-setuptools and python-setuptools-scm.
  [inputs]: Add python-{appdirs, distlib, filelock, six,
  importlib-metadata}.

gnu: python-xyz: Add python-filelock.

* gnu/packages/python-xyz.scm (python-filelock): New variable.

gnu: python-xyz: Add python-distlib.

* gnu/packages/python-xyz.scm (python-distlib): New variable.

gnu: ngless: Update to 1.1.0.

* gnu/packages/bioinformatics.scm (ngless): Update to 1.1.0.