Merge remote-tracking branch 'remotes/pmaydell/tags/pull-cocoa-20171107' into staging

cocoa queue:
 * make scrolling work in GUI monitor windows
 * change ungrab to ctrl-alt-g (matching gtk)
 * pass unused ctrl-alt combos to guest

# gpg: Signature made Tue 07 Nov 2017 10:15:00 GMT
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-cocoa-20171107:
  ui/cocoa.m: Send ctrl-alt key combos to guest if QEMU isn't using them
  ui/cocoa.m: move ungrab to ctrl-alt-g
  ui/cocoa.m: Make scrolling work again in GUI monitor windows

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