First steps towards remoting the SceneInspector.

We introduce an interface and client of the SceneInspector and
create a dummy, empty scene on the client side and so far only
set the proper scene rect on it.

In the future we will then forward interactions with that view
like zooming, rotating etc. to the server and render the scene
and propagate a pixmap of that to the client.

For in-process mode we still use the user scene directly.
Remote the scene view by forwarding a pixmap render of it.

This is far from optimal, as it will also be done in in-process mode
and just drain resources. Furthermore, we render also stuff which is
not (yet) visible on the client.
Do not run the costly renderScene for in-process mode.
Render the scene with taking the client transformation into account.

Also update when we change the transformation on the client view
or scroll in the view.

To prevent bad performance, we limit ourselves to 10fps for now.
Document the high-performance codepath for in-process scene inspector.
Add a comment on why we need an update timer.
Update pixmap position after resize.

This is required when the scene fits into the view without scroll-
bars and we resize the view. Then we still need to position and
potentially update the view.
Properly render selected item decoration for remote clients.

When an item is selected we signal the client the items's bounding
rect and ensure that is visible - just like we do for in-process.
Extend comment on todo.
Use setCurrentIndex to properly paint the decoration.
Fix various issues in the SceneModel as reported by ModelTest.

These where of various severity, but esp. the error in ::parent
resulted in multiple issues, esp. when trying to remote the
selection.
Select whole rows.
Add myself as author to some files I touched a lot
Also allow selecting an item from a remote client to show its deco.
Merge pull request #57 from KDAB/remote-graphicsview

Remote graphicsview