lzbench v1.5

• added the -r option : operate recursively on directories
• added the -j option : join files in memory but compress them independently (for many small files)
• lz5 updated to v2.0 RC2
• lz4 updated to v1.7.3
• zstd updated to v1.1.1
• libdeflate updated to v0.6
• csc updated to 2016-10-13
• improved PowerPC support
• fixed -m option (thanks to Julian Kunkel)