doc/aom_ctc: update for libvmaf v2.1.1

libvmaf: api v2.1.0, soname v1.1.0

libvmaf/README: mention SIMD is x86

Update version to 1.5.3; update CHANGELOG; add instruction for new re…

…lease. (Netflix#655)

Update meson.build to next release version (1.5.2) to sync libvmaf.pc…

… version

libvmaf.pc version wasn't properly sync when we moved from 1.3.15 to 1.5.1.
Increase meson.project_version() to resync release and .pc file.

Signed-off-by: Alexandre Demers <alexandre.f.demers@gmail.com>

Merge pull request Netflix#509 from Netflix/feature/update-version-ch…

…angelog-readme

Update CHANGELOG, README, VERSION.

Feature/update doc (Netflix#361)

* Add vmaf logo; add link to survey.

* Change logo size.

* Change logo size.

* Update logo size.

* Update CHANGELOG; bump up version to 1.3.15.

Update CHANGELOG and VERSION.

Update version to 1.3.13.

Update version to 1.3.12; update CHANGELOG, README, VERSION, libvmaf.pc.