Whenever this part of teh code runs, it has already been defauted. No need to default it again.
ENABLE_KVM replaces the DISABLE_KVM option that was present only in the init script. It did not have a corresponding conf.d option example. MACHINE allows for the specifcation of the system to emulate. CPU allows setting the specific cpu to emulate.
Make the new binary configurable. This allows multiple different vm targets using this same script.
Add additional note for zfs filesystems.
Some systems may have the ifconfig compatibility scripts diabled. This uses all ip commands instead.