Fix typo
Only run busybox-links fix on post-packages-configure
Minor tweaks

 * Duck can be used for things other than installations
 * Don't execute sleep unecessarily
Use sh for init scripts

 * Slightly faster
 * Consistent with debian init scripts
Re-add python-argparse as a dep, since duckdb uses
Merge pull request #6 from spotify/master

Cleanup tweaks