It may happen (especially when VM doesn't close cleanly and needs to be
killed) that qubesdb-daemon will not notice VM shutdown immediately.
Normally it would stop after 60s timeout, but speed it up in case of
system shutdown
QubesOS/qubes-issues#1425
Mostly done. Things still using xenstore/not working at all:
- DispVM
- qubesutils.py (especially qvm-block and qvm-usb code)
- external IP change notification for ProxyVM (should be done via RPC
service)
