This fixes a rare crash.

Reviewed-by: Kai Koehne

Some items are not movable, but the user should still be able
to select them in the form editor.

Best example are items inside a positioner.

Many qml documents have items outside of the root item area. The scene
rectangle is now much bigger so you can scroll the items around.

The custom notification code leads to hard readable code.

So the scene rectangle is the bounding rectangle of all items.

Reviewed-by: hjk

changing imports now resets the form editor

This notifies the views if the instance has be really instanced.

Because the order of the commands can be changed the reparenting was
changed. Now there is a command with the exact order of child items so
it should be much more correct.

The complete qml emulation layer (instances) is moved
into another external process (qmlpuppet).

Summary of architectural changes:

- Asynchronous messaging
    Handling commands and data transfer asynchronously reduces the
    amount of context switches between processes.

- Proxy classes for client process
    This classes abstract the inter process communication

- QVariant based command parsing and serialization
    Using LocalSocket in bidirectional manner for communications
    of commands and data transfer.

- Integer based identifier instead of ModelNode in client process
    The qml emulation layer (instances) has no more depencies to our
    internal data model.

- Timer based rendering
    Rendering in instances is controlled by a timer. Only dirty items
    are updated.

Bauhaus now uses only one single instance view.

Done by Marco Bubke

Before everything that was not children was ignored.

Thin of "back", "front" "flipableChildren"...

This is needed to suppert inline script function of Qml in the designer

Task-Number: BAUHAUS-673
Reviewed-by: kkoehne

The activation of the drag tool should not activate the base state
this is discussed in Bauhaus-600

Task-Number: BAUHAUS-566
Reviewed-by: kkoehne

Task-Id: BAUHAUS-475

Task-Id: BAUHAUS-427

Reviewed-by: thorbjorn

This adds a new "Design" mode that can be used to manipulate qml files
in a visual way. It will only get build if you have the declarativeui
module in Qt.

This is a squashed import from the Bauhaus project. Share & enjoy :)