gnu: Add python-snowballstemmer.

* gnu/packages/python.scm (python-snowballstemmer,
  python2-snowballstemmer): New variables.

Signed-off-by: Marius Bakke <mbakke@fastmail.com>

gnu: Use HTTPS for all sourceforge.net home pages.

* gnu/packages/admin.scm (mingetty, clusterssh)[home-page]: Use HTTPS.
* gnu/packages/audio.scm (libbs2b, soxr)[home-page]: Likewise.
* gnu/packages/bioinformatics.scm (bless)[home-page]: Likewise.
* gnu/packages/display-managers.scm (slim)[home-page]: Likewise.
* gnu/packages/games.scm (extremetuxracer)[home-page]: Likewise.
* gnu/packages/ghostscript.scm (gs-fonts)[home-page]: Likewise.
* gnu/packages/haskell.scm (ghc-regex-base, ghc-regex-posix,
ghc-regex-compat)[home-page]: Likewise.
* gnu/packages/image.scm (imlib2)[home-page]: Likewise.
* gnu/packages/libreoffice.scm (librevenge, libcmis, libodfgen, libmwaw)
[home-page]: Likewise.
* gnu/packages/linux.scm (hdparm, acpid, libavc1394, rng-tools)
[home-page]: Likewise.
* gnu/packages/mail.scm (esmtp)[home-page]: Likewise.
* gnu/packages/mp3.scm (ripperx)[home-page]: Likewise.
* gnu/packages/onc-rpc.scm (libtirpc)[home-page]: Likewise.
* gnu/packages/perl.scm (perl-czplib)[home-page]: Likewise.
* gnu/packages/python.scm (python-pyasn1-modules)[home-page]: Likewise.
* gnu/packages/xdisorg.scm (xosd)[home-page]: Likewise.

gnu: Add python-xdo.

* gnu/packages/python.scm (python-xdo): New variable.
(python2-xdo): Use package-with-python2.

gnu: python2-xdo: Update to 0.3.

* gnu/packages/python.scm (python2-xdo): Update to 0.3.

gnu: python-s3transfer: Update to 0.1.10.

* gnu/packages/python.scm (python-s3transfer): Update to 0.1.10.

gnu: python-greenlet: Update to 0.4.11.

* gnu/packages/python.scm (python-greenlet): Update to 0.4.11.

gnu: python-mako: Update to 1.0.6.

* gnu/packages/python.scm (python-mako): Update to 1.0.6.

gnu: awscli: Update to 1.11.35.

* gnu/packages/python.scm (awscli): Update to 1.11.35.

gnu: python-werkzeug: Update to 0.11.15.

* gnu/packages/python.scm (python-werkzeug): Update to 0.11.15.

gnu: python-backports-abc: Update to 0.5.

* gnu/packages/python.scm (python-backports-abc): Update to 0.5.

gnu: python-decorator: Update to 4.0.10.

* gnu/packages/python.scm (python-decorator): Update to 4.0.10.

gnu: python-pycparser: Use ‘modify-phases’ syntax.

* gnu/packages/python.scm (python-pycparser)[arguments]: Use
‘modify-phases’.

gnu: python-pycparser: Update to 2.17.

* gnu/packages/python.scm (python-pycparser): Update to 2.17.

gnu: python-pyicu: Update to 1.9.5.

* gnu/packages/python.scm (python-pyicu, python2-pyicu): Update to 1.9.5.
[source]: Use pypi-uri.

gnu: python-ndg-httpsclient: Use pypi-uri.

* gnu/packages/python.scm (python-ndg-httpsclient, python2-ndg-httpsclient)
[source]: Use pypi-uri.

gnu: python-graphql-relay: Update to 0.4.5.

* gnu/packages/python.scm (python-graphql-relay): Update to 0.4.5.

gnu: python-freezegun: Update to 0.3.8.

* gnu/packages/python.scm (python-freezegun): Update to 0.3.8.

gnu: python-ply: Update to 3.9.

* gnu/packages/python.scm (python-ply): Update to 3.9.
[source]: Use pypi-uri.

gnu: python-pyquery: Update to 1.2.17.

* gnu/packages/python.scm (python-pyquery): Update to 1.2.17.

gnu: python-click-log: Update to 0.1.8.

* gnu/packages/python.scm (python-click-log): Update to 0.1.8.