The patch included in this commit fixes several inconveniences with regards to
the path infrastructure.
First, install-vmrc.sh now uses the path defined in vm.conf -- so it's a good
idea to edit that before installing.
Second, vm.conf allows to specify a dataset to use with bhyve. So now, to use
setups like tank/bhyve/openbsd6, you no longer need to specify
host_zpool="tank/bhyve".
Third, add the possibility for non-FreeBSD VMs to be backed by a ZVOL image.
This check has been copied from another part of vmrc and should probably be
refactored into a proper subroutine in the next version of this script.
Changes to templates
* install-templates now uses paths setup in ../vm.conf
* add OpenNode template (http://opennodecloud.com/about/)