[babl] Created tag BABL_0_1_68

[Øyvind "pippin" Kolås <ok src gnome org>]

The unsigned tag 'BABL_0_1_68' was created.

Tagger: Øyvind Kolås <pippin gimp org>
Date: 1564059562 +0200

    0.1.68

Changes since the last tag 'BABL_0_1_66':

Ell (4):
      configure.ac: clean up SSE config
      configure.ac, meson, cpu-accel: add AVX2 detection
      extensions: add AVX2 linear-float -> gamma-u8 conversions
      extensions: distribute avx2-int8-tables.h

Elle Stone (1):
      Add Yu'v' (CIE 1976 UCS) to babl CIE color spaces

Félix Piédallu (2):
      Fix git-version.h handling
      force generate git-version.h before copying

Thomas Manni (1):
      babl: performance improvement in model-gray

Øyvind Kolås (52):
      post release version bump
      babl: symmetric conversions between associated and separate alpha.
      extensions: fix up some lingering references to babl_alpha_avoid_zero
      meson: add transparent_symmetry test
      babl/base: use symmetric alpha transformations for CMYK
      docs: update
      docs: add section about symmetric alpha transforms
      tests: rename from transparent_symmetry to alpha_symmetric_transform
      docs: add tools dir to dir-overview
      AUTHORS: add some missing entries
      meson: fix typoed filename
      babl: make model_is_symmetric test adapt tolerance for high values
      extensions/CIE.c: improve handling of near zero values
      babl-space: 0 initialize temporary stack allocated BablSpace instances
      babl-fish-path: cache a local sRGB space instance
      babl-fish: use abstraction for checking if space is cmyk
      babl-space: indentation improvements
      babl-space: add universal convertors between linear and nonlinear
      docs: remove reference to non-existing file build-docs.sh
      docs: add separate pages for CMYK, ColorManagement and alpha
      meson: adapt to changes in docs build
      docs: improve the generated reference
      babl: replace premultiplied with associated in BablModelFlags
      extensions/cairo: s/premul/assoc/ in function names
      extensions/gimp-8bit: s/premul/assoc/ in function names
      extensions/sse2-float: s/premul/assoc/ in function names
      base: s/premultiplied/associated_alpha/
      docs: rename vocabulary page to reference
      docs: dist Reference.html
      docs: update meson.build
      docs: improve generated reference
      extensions/CIE: add some documentation overrides
      docs: s/git.gnome.org/gitlab.gnome.org/
      babl-space: do not use universal rgb sse converter for non-sse path
      docs: refer to Y in generated reference as Luminance
      docs: start adding a glossary
      extensions/HSV: add documentation for model
      meson: require meson version 0.49.0
      build (docs): add Glossary.html to BUILT_EXTRA_DIST
      extensions/HSV: update model docs
      extensions/HSL: add model doc string
      docs: add OldNews page
      HCY: convert luminance relative to RGB chromaticities
      update NEWS
      AUTHORS: update
      meson: fix mistake in add_dist_script
      docs: add a couple of entries to glossary
      docs: remove wrong refernces to old versions
      docs: remove duplicate files
      INSTALL.in: document meson build instead of autotools build
      NEWS: update
      release 0.1.68