v1.3.3
fix a subtle issue in continue mode
Merge pull request #958 from facebook/continueCCtx
re-added test case
fixed zbufftest
no longer supported starting C++17
fixed a bunch of headers after license change (#825)
makes it possible to compile libzstd in single-thread mode without zstdmt_compress.c (#819)
Update BUCK files
programs/Makefile : better support for GNU conventions
updated pkg config file
version bump to v1.3.3