Merge branch 'staging'

gnu/packages/base.scm

gnu/packages/certs.scm

gnu/packages/check.scm

gnu/packages/cups.scm

gnu/packages/databases.scm

gnu/packages/freedesktop.scm

gnu/packages/gl.scm

gnu/packages/glib.scm

gnu/packages/gtk.scm

gnu/packages/haskell.scm

gnu/packages/imagemagick.scm

gnu/packages/nss.scm

gnu/packages/onc-rpc.scm

gnu/packages/perl.scm

gnu/packages/python-xyz.scm

gnu/packages/sphinx.scm

gnu/packages/textutils.scm

gnu/packages/time.scm

gnu/packages/tls.scm

gnu/packages/vulkan.scm