Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Thu 03 Dec 2015 04:59:48 GMT using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/block-pull-request:
  iotests: Add regresion test case for write notifier assertion failure
  iotests: Add "add_drive_raw" method
  block: Don't wait serialising for non-COR read requests
  iothread: include id in thread name

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