Code review comment for lp://staging/~mabac/linaro-image-tools/snowball-android-startfiles-hack

Wow, nice, lots of new tests! This looks quite good; the only comment I have is about snowball_config(chroot_dir), which has no docstring and return a two-tuple where one value is a hard-coded boolean so there's no way to know what it means. I'd prefer if the hard-coded value were in a class attribute and snowball_config(chroot_dir) returned just the path to the config dir, but having just a docstring on snowball_config() would be ok as well.