The internal on__MenuClosed signal has been renamed
to onAboutToHide in qtquickcontrols. Also update some
import versions while we're at it.
This patch also adds examples OSX application bundles
to .gitignore which only contained the unix binaries.

Change-Id: If1d91cb65987dda6d0e10794c1649b1b4e1ccde3
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@theqtcompany.com>