See qcocoaaccessiblity.h for details.
For now only the first level of the hierarchy is
made accessible.
Also add tools/accessibilityinspector which is an
utility for inspecting and debugging the Qt
accessibility tree.
Change-Id: Iff520bec26b3761feb0c2e00471feb379daaa735
Reviewed-by: Morten Johan Sørvig <morten.sorvig@nokia.com>