As a matter of fact, there are two frame formats defined by Zstandard: Zstandard frames and Skippable frames. So we should probably support zstd algorithms with skippable frames. See https://tools.ietf.org/id/draft-kucherawy-dispatch-zstd-00.html#rfc.section.2 for more details. Signed-off-by: Da McGrady <dabkb@aol.com>