adding better doc string with example output:

raw:    423 MB of FC data, 1.000 compression, 0.000 seconds --> inf MB/sec compression, 0.000 seconds --> 0.000 MB/sec decompression
xz:     34 MB of FC data, 0.081 compression, 164.662 seconds --> 0.208 MB/sec compression, 3.169 seconds --> 10.786 MB/sec decompression
gz:     75 MB of FC data, 0.178 compression, 17.321 seconds --> 4.358 MB/sec compression, 2.584 seconds --> 29.220 MB/sec decompression
bz2:    38 MB of FC data, 0.090 compression, 44.640 seconds --> 0.857 MB/sec compression, 10.356 seconds --> 3.696 MB/sec decompression
snappy: 134 MB of FC data, 0.318 compression, 0.532 seconds --> 253.226 MB/sec compression, 10.356 seconds --> 13.001 MB/sec decompression