zstandard: vendor python-zstandard 0.12...
zstandard: vendor python-zstandard 0.12
The upstream source distribution from PyPI was extracted. Unwanted
files were removed.
The clang-format ignore list was updated to reflect the new source
of files.
test-repo-compengines.t was updated to reflect a change in behavior
of the zstd library.
The project contains a vendored copy of zstandard 1.4.3. The old
version was 1.3.8. This should result in some minor performance wins.
# no-check-commit because 3rd party code has different style guidelines
Differential Revision:
https://phab.mercurial-scm.org/D6858
