Added : zbuff.c to library; reported by Yipei Zhang
Added : zbuff.c to library; reported by Yipei Zhang

inikep/zstd,inikep/zstd,ds77/zstd,Cyan4973/zstd,Cyan4973/zstd,ds77/zstd,ds77/zstd,Majlen/zstd,Cyan4973/zstd,inikep/zstd,ds77/zstd,Majlen/zstd,Majlen/zstd,Majlen/zstd,Cyan4973/zstd,Cyan4973/zstd,inikep/zstd