A new suspend/hibernate infrastructure

In order to really make sense, the hibernate description needs to note that the restoration
process works by booting the system into a state that's able to load the stored state and then
transfer control to it.

The reason for "quiesce" is that the drivers used in the temporary system have to finish up
what they're doing before they get replaced with the loaded image and put the devices into a
state such that the drivers from the saved image (which have no idea what the temporary system
did) can get them working again in some sane fashion. That is, the kernel image that the user
cares about never calls quiesce() at all, either before or after shutting down.