Merge remote-tracking branch 'mdroth/qga-pull-3-11-2013' into staging

# By Laszlo Ersek (3) and others
# Via Michael Roth
* mdroth/qga-pull-3-11-2013:
  qga: implement qmp_guest_set_vcpus() for Linux with sysfs
  qga: implement qmp_guest_get_vcpus() for Linux with sysfs
  qga: introduce guest-get-vcpus / guest-set-vcpus with stubs
  qga: add guest-set-time command
  qga: add guest-get-time command
  qemu-ga: use key-value store to avoid recycling fd handles after restart
  qemu-ga: make guest-sync-delimited available during fsfreeze
  qemu-ga: fix confusing GAChannelMethod comparison
  qga: cast to int for DWORD type