Because I'm not familiar with Rust, when I was working on
https://github.com/bootandy/dust/pull/390 I didn't realize that the
completions were auto-generated via clap. I'm sorry. This redoes it
with clap.
This improves not only the completions but also the --help and the
man page. Also the --output-format flag will raise an error if the
given value is invalid.
add new option: --output-format this controls how the output is
summarised and takes:
nothing = default behaviour
si = SI units (same as old --si flag)
b = bytes
kb = kb
kib = si kb
mb = mb
mib = si mb
....etc
If a user reports a crash from stacksize - we can try different stack
memory sizes to try and figure out the cause.
Do not try and initialise rayon on 32 bit builds
Fix rayon initialisation, may not have been called before due to badly
formed closure
