Merge remote-tracking branch 'mdroth/tags/qga-pull-2017-04-25-v2-tag' into staging

qemu-ga patch queue

* new commands: guest-get-timezone, guest-get-users, guest-get-host-name
* fix hang on w32 when stopping qemu-ga service while fs frozen
* fix missing setting of can-offline in guest-get-vcpus
* make qemu-ga VSS w32 service on-demand rather than on-startup
* fix unecessary errors to EventLog on w32
* improvements to fsfreeze documentation

v2:
 * document 'zone' field of guest-get-timezone as informational-only
   (Daniel, Eric)
 * fix build error for glib < 2.32 (Peter)

# gpg: Signature made Thu 27 Apr 2017 06:43:42 AM BST
# gpg:                using RSA key 0x3353C9CEF108B584
# gpg: Good signature from "Michael Roth <flukshun@gmail.com>"
# gpg:                 aka "Michael Roth <mdroth@utexas.edu>"
# gpg:                 aka "Michael Roth <mdroth@linux.vnet.ibm.com>"
# Primary key fingerprint: CEAC C9E1 5534 EBAB B82D  3FA0 3353 C9CE F108 B584

* mdroth/tags/qga-pull-2017-04-25-v2-tag:
  qga: Add `guest-get-timezone` command
  qga: Add 'guest-get-users' command
  qga: improve fsfreeze documentations
  qga: Add 'guest-get-host-name' command
  qga-win: Fix Event Viewer errors caused by qemu-ga
  qga-win: Fix a bug where qemu-ga service is stuck during stop operation
  qga-win: Enable 'can-offline' field in 'guest-get-vcpus' reply
  qemu-ga: Make QGA VSS provider service run only when needed

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>