Added firstboot which is called from joyent_rc.local and set-hostid script. The firstboot script calls format-secondary-disk and set-hostid once only.
Added firstboot which is called from joyent_rc.local and set-hostid
script. The firstboot script calls format-secondary-disk and set-hostid
once only.

This addesses IMAGE-446 and IMAGE-441.

joyent/sdc-vmtools,joyent/sdc-vmtools-lx-brand,rcj4747/sdc-vmtools-lx-brand