Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2016-07-06' into staging

QAPI patches for 2016-07-06

# gpg: Signature made Wed 06 Jul 2016 10:00:51 BST
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2016-07-06:
  replay: Use new QAPI cloning
  sockets: Use new QAPI cloning
  qapi: Add new clone visitor
  qapi: Add new visit_complete() function
  tests: Factor out common code in qapi output tests
  tests: Clean up test-string-output-visitor
  qmp-output-visitor: Favor new visit_free() function
  string-output-visitor: Favor new visit_free() function
  qmp-input-visitor: Favor new visit_free() function
  string-input-visitor: Favor new visit_free() function
  opts-visitor: Favor new visit_free() function
  qapi: Add new visit_free() function
  qapi: Add parameter to visit_end_*
  qemu-img: Don't leak errors when outputting JSON
  qapi: Improve use of qmp/types.h

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