For certain swap/overcommit settings (e.g. when overcommit is disabled
on a real-time system), we need to limit the stack size used by
initscripts. When the STACK_SIZE environment variable is set (usually
in /etc/default/rcS), ulimit the stack size to the value specified.
Make the stack size ulimit a soft limit, which allows the user to
increase the stack size where required without having to run the
respective application as root.
