Various additions including Soekris

*  Addition of the build for Soerkris, including kernel configs for FreeBSD 8,9,10
*  -e <address> flag added, to email progress updates on long, unattended builds
*  -u flag added to allow updating the tree before building, also for unattended builds
*  added /lib/subversion.sh; subversion methods, specifically for updating the tree
*  added /lib/email.sh to; email methods
*  added /lib/gzip.sh to support gzipping of final images
*  added /lib/os.h; provides methods for determining the target OS version and the location of binaries on the OBJ tree, such as /boot/mbr
*  added /lib/pw.sh to support adding a default non-root user who is a member of wheel, to enable logging int via ssh
*  generated image name now contains OS version