add notes on testing an upgrade
add notes on testing an upgrade

joyent/sdc-headnode,joyent/sdc-headnode,numericillustration/sdc-headnode,joyent/sdc-headnode,kaizengarden/sdc-headnode,kaizengarden/sdc-headnode,kaizengarden/sdc-headnode,kaizengarden/sdc-headnode,numericillustration/sdc-headnode,joyent/sdc-headnode,numericillustration/sdc-headnode