Thank Marek.

Update 'THANKS'.

* THANKS: Correct the email address I use for Guix work.

Thank Taylan and Alex.

Thank Benno.

Merge branch 'master' into core-updates

Thank Carlos.

Merge branch 'master' into core-updates

Thank Niels.

Thank Kete.

Merge branch 'master' into core-updates

Thank Jeffrin and David.

Update 'AUTHORS'.

* AUTHORS: Add Alex, Joshua, and Aljosha.

Merge branch 'master' into core-updates

Thank Cyrill.

Thank Matthias and Yutaka.

gnu: Add pspp.

* gnu/packages/maths.scm (pspp): New variable.
* THANKS: Thank John Darrington for help with debugging.

gnu: Add libextractor.

* gnu/packages/gnunet.scm: New module.
* gnu-system.am (GNU_SYSTEM_MODULES): Add module.
* THANKS: Thank Christian Grothoff for help with debugging.

Thank the translators.

Import (guix hash) in build-aux/download.scm.

* build-aux/download.scm: Import (guix hash).
  Reported by Matthew Lien <bluet@bluet.org>.

Fix name of Alexandru.