vmm/virtualbox: Add noresume VMM option
vmm/virtualbox: Add noresume VMM option

- Add "noresume" option, which causes the VirtualBox driver to register
the VM and then wait for SIGINT rather than resuming the parcel.  This
allows the user to configure machine settings using the VirtualBox GUI
(provided the parcel is powered off) rather than needing to edit the
machine XML by hand.

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr