Merge branch 'dev' of https://github.com/facebook/zstd into ldm-mergeDev

diff --cc lib/common/zstd_internal.h
Simple merge

diff --cc lib/compress/zstd_compress.c
Simple merge

diff --cc lib/compress/zstd_compress.h
Simple merge

diff --cc lib/compress/zstd_double_fast.c
Simple merge

diff --cc lib/compress/zstd_double_fast.h
Simple merge

diff --cc lib/compress/zstd_fast.c
Simple merge

diff --cc lib/compress/zstd_fast.h
Simple merge

diff --cc lib/compress/zstd_lazy.c
Simple merge

diff --cc lib/compress/zstd_lazy.h
Simple merge

diff --cc lib/compress/zstd_opt.c
Simple merge

diff --cc lib/compress/zstd_opt.h
Simple merge

diff --cc lib/compress/zstdmt_compress.c
Simple merge

diff --cc lib/zstd.h
Simple merge

diff --cc programs/bench.c
Simple merge

diff --cc programs/bench.h
Simple merge

diff --cc programs/fileio.c
Simple merge

diff --cc programs/fileio.h
Simple merge

diff --cc programs/zstdcli.c
Simple merge

diff --cc tests/zstreamtest.c
Simple merge