Merge remote-tracking branch 'remotes/armbru/tags/pull-monitor-2015-09-04' into staging

Monitor patches

# gpg: Signature made Fri 04 Sep 2015 12:40:11 BST using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-monitor-2015-09-04:
  hmp: add info iothreads command
  qmp-shell: add documentation

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>