These test artifacts are used by the upload test.

• raw.img
  1MB of zeroes
  dd if=/dev/zero of=raw.img bs=1M count=1

• raw.img.bz
  raw.img compressed with bzip2
  bzip2 < raw.img > raw.img.bz2

• raw.img.gz
  raw.img compressed with gzip
  gzip < raw.img > raw.img.gz

• raw.img.xz
  raw.img compressed with xz
  xz < raw.img > raw.img.gz