further improved parallel init, with some results

[Petter Reinholdtsen]

[Olivier Sessink]
> so paralell execution reduces the startup time with 22% on this box

Are you using sid?  If so, please test the shell-based parallel
execution as well (set CONCURRENCY=shell in /etc/default/rcS), to
check how much is gained by using a compiled program to run the
scripts.  I am curious how much of thei gain come from
parallelization, and how much comes from using a compiled program to
run the scripts. :)

Did you try to use insserv to reorder the boot scripts based on
dependency information?  Did you and insserv agree on what could be
executed in parallel?