rc.{local,securelevel,shutdown} become examples. If versions of them

rc.{local,securelevel,shutdown} become examples.  If versions of them
are created in /etc, they are executed (they used to be sourced) to
avoid polluting the rc variable space.  The powerdown= and securelevel=
features are removed; they are likely only used by 2 people.  the
secureleve is now always raised; this is the only sensible default.
ok ajacoutot