Merge branch 'core-updates'

gnu: ffmpeg: Drop old version 2.2.

* gnu/packages/video.scm (ffmpeg-2.2): Remove variable.
  (ffmpeg)[arguments]: Drop LDFLAGS environment variable needed only for
  older versions.

gnu: vlc: Update to 2.2.0.

* gnu/packages/video.scm (vlc): Update to 2.2.0.
  [inputs]: Switch from ffmpeg-2.2 to latest one.

gnu: ffmpeg: Allow tests to run from the build tree.

* gnu/packages/video.scm (ffmpeg)[arguments]: Add 'set-ld-library-path'
  phase.

gnu: ffmpeg: Use 'modify-phases'.

* gnu/packages/video.scm (ffmpeg)[arguments]: Use 'modify-phases'
  instead of 'alist-cons-after' et al.

gnu: libvpx: Augment rpath.

Fixes <http://bugs.gnu.org/20055>.

* gnu/packages/video.scm (libvpx)[arguments]: Set LDFLAGS to
  '-Wl,-rpath=$out/lib' in configure phase.

gnu: Add missing quotes in phase names passed to 'modify-phases'.

This is a followup to f8503e2.

* gnu/packages/gnome.scm (glib-networking): Add missing quotes before
  phase names passed to 'modify-phases'.
  (libsoup): Likewise.
  (gnome-terminal): Likewise.
  (colord): Likewise.
  (geoclue): Likewise.
* gnu/packages/gtk.scm (at-spi2-core, at-spi2-atk): Likewise.
* gnu/packages/haskell.scm (ghc-network): Likewise.
* gnu/packages/imagemagick.scm (perl-image-magick): Likewise.
* gnu/packages/video.scm (aalib): Likewise.
* gnu/packages/web.scm (nginx): Likewise.

Merge branch 'master' into core-updates

gnu: Add livestreamer.

* gnu/packages/video.scm (livestreamer): New variable.

gnu: Add aalib.

* gnu/packages/video.scm (aalib): New variable.

gnu: libva: Fix 'license' field.

* gnu/packages/video.scm: Import (guix licenses) with the 'license:'
  prefix and adjust 'license' fields accordingly.  Fixes a bug whereby
  libva was referring to the 'expat' package instead of the 'expat'
  license.

gnu: Refer to %GNU-BUILD-SYSTEM-MODULES instead of listing modules.

* gnu/packages/cdrom.scm (cdparanoia)[arguments]: Refer to
  %GNU-BUILD-SYSTEM-MODULES instead of providing the actual list.
* gnu/packages/emacs.scm (magit, emacs-w3m, emacs-wget, emms):
  Likewise.
* gnu/packages/haskell.scm (ghc): Likewise.
* gnu/packages/samba.scm (samba): Likewise.
* gnu/packages/video.scm (ffmpeg): Likewise.

utils: 'modify-phases' no longer introduces quotes.

Suggested by Taylan Ulrich Bayırlı/Kammer <taylanbayirli@gmail.com>.

* guix/build/utils.scm (%modify-phases): Remove quotes.
* guix/build/cmake-build-system.scm (%standard-phases): Adjust
  accordingly.
* guix/build/glib-or-gtk-build-system.scm (%standard-phases): Likewise.
* guix/build/gnu-dist.scm (%dist-phases): Likewise.
* guix/build/perl-build-system.scm (%standard-phases): Likewise.
* guix/build/python-build-system.scm (%standard-phases): Likewise.
* guix/build/ruby-build-system.scm (%standard-phases): Likewise.
* guix/build/waf-build-system.scm (%standard-phases): Likewise.
* gnu/packages/bash.scm, gnu/packages/code.scm, gnu/packages/gl.scm,
  gnu/packages/gnome.scm, gnu/packages/graphics.scm,
  gnu/packages/image.scm, gnu/packages/key-mon.scm,
  gnu/packages/ocr.scm, gnu/packages/plotutils.scm,
  gnu/packages/search.scm, gnu/packages/video.scm: Likewise.

Merge branch 'master' into core-updates

gnu: liba52: Pass --build to configure.

* gnu/packages/video.scm (liba52)[arguments]: Pass --build to configure.

gnu: Add mpv.

* gnu/packages/video.scm (mpv): New variable.

gnu: Add vapoursynth.

* gnu/packages/video.scm (vapoursynth): New variable.

gnu: Add libva.

* gnu/packages/video.scm (libva): New variable.

Merge branch 'master' into core-updates

gnu: Add mplayer2.

* gnu/packages/video.scm (mplayer2): New variable.
* gnu/packages/patches/mplayer2-theora-fix.patch: New file.
* gnu-system.am (dist_patch_DATA): Add it.