Move tardirs=, vnddirs=, and mfsdirs= to etc/rc.flashrd.sub, for both
runtime usage (/etc/rc) and for image creation (flashrd/cfgflashrd) usage.

This way we have one place to change variables, not many. There is another
copy of vnddirs= in stand/rc, and this has to remain. RC notes are adjusted.

Also, put flashrd-specific init stuff in own rc.flashrd.* config files. Call
those from example rc.{conf.local,local,shutdown} files. That way, upgrades
through onetime.tgz can include one line in rc.{conf.local,local,shutdown}
and get the full flashrd upgrade with no manual merging of any data. This
is simply an extension of what was done in the last few commits.
Copy new files to image and proper printing for error line tmpdir
reverse think-o
Stop lying. Better notes on what variables are important where and when.
flashrd 1.3
and even more explicit definition of flashrd variable usage,
mainly defined in etc/rc.flashrd.sub
OpenBSD has gone double-triple X as of mktemp.c r1.16
"Require that the template include at least 6 trailing Xs to match
POSIX mkstemp/mkdtemp.  Check before the call to mkstemp/mkdtemp
so we can give a better error message than "invalid argument"."

noticed by braddeicide https://github.com/yellowman/flashrd/issues/9
Don't extract extra tgz's until / is mounted r/w

This should mean the tardirs are now extracted and we can update those if so
desired as well as write to / if need be.
Add a '/flashrd.site' hook after onetime.tgz has been extracted

While it is possible to put everything staticly into onetime.tgz, some things
are easier to do in a script such as updating /etc/rc.conf.local.

An example of what a flashrd.site might contain:

ping -c 1 192.168.40.1 > /dev/null || dhclient em0
export PKG_PATH=ftp://ftp.openbsd.org/pub/OpenBSD/`uname -r`/packages/`machine`
pkg_add nrpe nagios-plugins check_hw_sensors
pkg_add nsh

echo sshd_flags=NO >>/etc/rc.conf.local
echo pf=NO >>/etc/rc.conf.local
echo inetd=NO >>/etc/rc.conf.local

echo "/usr/local/bin/nsh -i /flash/nshrc" >> /etc/rc.local
rm /usr/local/bin/save.sh
sed -e 's/etc/flash/' < /usr/local/share/save-rw.sh > /usr/local/bin/save.sh
Merge pull request #11 from afresh1/master

onetime.tgz enhancements - second try
Merge pull request #1 from yellowman/master

Pull in changes from main trunk